Patent Publication Number: US-7218238-B2

Title: Fire alarm system with method of building occupant evacuation

Description:
FIELD OF THE INVENTION 
   The present invention generally relates to a building fire alarm evacuation system for alerting individuals within a protected area of the presence of an emergency situation. More particularly, the present invention relates to the interaction of smoke detectors within the protected premise and audible and visible notification devices located within the protected premise, in which the activation of both the audible and visible devices are sequenced in a predefined pattern in response to the activation of the smoke detector. The sequence of sound and light patterns guide occupants to areas of safety in low/no visibility conditions. 
   BACKGROUND OF THE INVENTION 
   Fire alarm systems used in buildings and such are designed to save lives and comprise a number of components including devices such as smoke and heat sensors, and audible and visible indicators. 
   Indicators range from audio devices such as speakers, bells, horns, and sirens to visual devices such as incandescent lights, strobe lights, and illuminated exit signs. 
   For instance, prior art consists of a number of horns, sirens, bells, or voice message devices, which are strategically placed throughout a building and connected to the control panel of the fire alarm system. Upon the detection of smoke or fire, the audible device would activate and serve as an audible indicator of an emergency situation. 
   Alerting technology may incorporate the use of a strobe light, and like the audible device, is connected to the fire alarm control system and functions to serve as a visual indicator of an emergency situation. 
   The strobe light, however, has a different impact than that of the audible device. For example, the strobe light is better able to notify those with a hearing disability about the presence of an emergency. Furthermore, the light is effective in nighttime situations especially when the individual is outside the audible device&#39;s range. This is especially true when the audible device malfunctions and is unable to produce an audible sound. As a result of the mechanical failure possibility, many fire alarm systems incorporate a strobe light serving the dual purpose as detailed. In fact, many local towns or municipalities have mandated by law the use of both strobes and audible devices to alert individuals as to an emergency. 
   Placement of the devices in a building is generally determined by a variety of factors such as floor plans, hallways and room locations, elevator locations, exit locations, fire walls, etc. For instance, some buildings have a greater capacity to deliver sound, or reflect the strobe light based upon the buildings interior make-up. 
   The operating characteristics of audible and visual signals determine how occupants will hear and see them. These characteristics include the sound intensity and frequency, color of light and its intensity, flash duration, and flash repetition rate. Different buildings and environments require different needs. 
   The primary purpose of the fire alarm system is to alert the occupants and evacuate or lead them to safety. Sounding a general alarm tone or pre-recorded voice message accompanied with flashing lights may accomplish this goal in good visibility, but in cases where visibility is impaired or non-existent, it may not. 
   For example, an occupant of a hotel room may hear an evacuation signal in the middle of the night, open the room door, and must decide to take a left or right down the hallway to get to safety and has a fifty percent chance that he will select the correct direction. If he chooses the wrong direction, he may lead directly to the fire. A wrong decision may lead to toxic exposure and be fatal. When visibility is reduced or non-existent due to airborne particulates of combustion, the situation is more critical and a timely direct path to egress is monumental. 
   Accordingly, it is desirable to provide a method and apparatus that indicate a direct and timely path of egress in an emergency situation. 
   SUMMARY OF THE INVENTION 
   The foregoing needs are met, to a great extent, by the present invention, wherein in one aspect an apparatus is provided that in some embodiments provides a direct and timely path of egress in an emergency situation. 
   In accordance with one aspect of the present invention, a fire alarm system is provided, comprising a controller; a plurality of detectors; a plurality of audible devices; and a plurality of visible devices, wherein the controller is electrically connected to the detectors and controls the audible devices and the visible devices. The fire alarm system also includes the controller having memory and a delay control. 
   In accordance with another aspect of the present invention, a method of controlling a fire alarm system is provided comprising assigning an address to each of a plurality of detectors, audible devices and visible devices; storing said address of each detector, audible device and visible device; correlating each stored addresses to a physical location; activating a general alarm on each audible device and each visible device; determining activated detector&#39;s address and physical location; determining correlation of activated detector in proximity to each audible device and each visible device; assigning a sequence number to each audible device and each visible device; and activating each audible device and visible device according to their sequence number. 
   In accordance with still another aspect of the present invention, a fire alarm system is provided, comprising means for assigning an address to each of a plurality of detectors, audible devices and visible devices; means for storing said address of each detector, audible device and visible device; means for correlating each stored addresses to a physical location; means for activating a general alarm on each audible device and each visible device; means for determining activated detector&#39;s address and physical location; means for determining correlation of activated detector in proximity to each audible device and each visible device; means for assigning a sequence number to each audible device and each visible device; and means for activating each audible device and each visible device according to their sequence number. 
   Therefore, there is a need for a fire alarm system, which incorporates the use of an addressable fire detector, and an addressable audio and visual alert system that provides the occupant a directional path to areas of safety including other rooms, floors, or exits. The path may be dynamic and dependant on the initial fire location, and may direct occupants away from the fire origin to areas of safety. 
   There has thus been outlined, rather broadly, certain embodiments of the invention in order that the detailed description thereof herein may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional embodiments of the invention that will be described below and which will form the subject matter of the claims appended hereto. 
   In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting. 
   As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a diagrammatic representation of the detection and control system according to a preferred embodiment of the invention. 
       FIG. 2  is a diagrammatic representation illustrating the sequential signal flow from one alarm device to another thereby creating a virtual directional motion according to  FIG. 1 . 
       FIG. 3  is flowchart illustrating steps that may be followed in accordance with the preferred embodiment of  FIG. 1 . 
   

   DETAILED DESCRIPTION 
   The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. Referring to  FIG. 1 , an embodiment in accordance with the present invention provides a controller  110  having a signaling delay control  160  and controller memory  150 , a plurality of smoke and/or heat detectors  120 , a plurality of audible devices  140  which may include sirens, preferably, or public announcement (PA) devices and the like, and a plurality of visible devices  130  which may include strobes, preferably, or fluorescent lighting and the like. The signaling delay control  160  may be configured to time the sequence of activation for the audible devices  140  and/or the visible devices  130 . The present invention is a fire alarm system  100 , which incorporates the use of a plurality of addressable smoke and/or heat detectors  120 , and an addressable audio devices  140  and visual alert devices  130  that provides the occupant a directional path to areas of safety including other rooms, floors, or exits. The path may be dynamic and dependant on the initial fire location, and may direct occupants away from the fire origin to areas of safety as an alarm situation progresses or intensifies 
   The addressable feature of the smoke and/or heat detectors  120  and the audible devices  140  and visible devices  130  provides the ability to assign an address and thereby even a physical location to each. This assigned address and physical location can be stored in the controller memory  150  for later access and processing upon an alarm situation being detected or present. 
   The fire alarm system  100  has the capability and configuration to locate the actual fire hazard distinctly and directly. Fire alarm system  100  can also direct the egress evacuation to a safe location away from the detected fire hazard location in a clear and distinct manner via the audible devices  140  and visible devices  130  sequencing away from the direction of possible harm or fire. The fire alarm system  100  has the ability to react and be dynamic as the dynamics of the fire hazard changes or grows in order to direct occupants to safety. 
   Referring to  FIGS. 2 and 3 , in accordance with one embodiment of the present invention, a combination smoke and/or heat detector devices  120 , and a visual alarm signaling device  130 , and an audible alarm signaling device  140 , is installed at strategic locations  210 ,  220 ,  230 ,  240 . These locations  210 ,  220 ,  230 ,  240  may be in proximity to an exit or exits as needed. The smoke/heat detector devices  120  are assigned a unique identity or address  305  that indicates it&#39;s physical location  315  to the controller  110 . Similarly, the audible devices  140  and visual devices  130  are each assigned a unique identity  305  that allows an electrical signal or command to be sent from the controller  110  to activate the devices  130 ,  140  accordingly. When smoke or fire detectors  120  are activated, the controller  110  determines the location  210 ,  220 ,  230 ,  240 , defines the path of exit  250 , compiles the sequence of commands  350 ,  360  to be sent to the audible devices  140  and visible devices  130  which in turn lays out the path  250 , audibly and visibly, of egress to the occupant(s) in the protected area. 
   The basis for providing the illusion of directional movement for the audible devices  140  and visible devices  130  can best be demonstrated in  FIG. 2 . In this example, each circle represents a single location  210 ,  220 ,  230 ,  240  and would represent an addressable audible device  140  and an addressable visible device  130 , or may be either as well. If a command is sent to all the devices  130 ,  140  at location  210 , followed by a delay signal  160 , followed by a command  335  sent to all devices  130 ,  140  at location  220 , and so on, the perception of rotational movement is created, similar to a marquis sign. This same principle applies to hallways, open areas, etc. 
   Referring to  FIG. 3 , in operation, the control process  300  assigns an address  305  to each detector  120 , audible device  140  and/or visible device  130  and then these addresses are stored  310  by the controller  110  in the controller memory  150  of fire alarm system  100 . Next, these addresses are correlated and re-stored to the actual physical locations  315  of each device  120 ,  130 ,  140 . The controller  110  now monitors  320  each detector  120  for alarm. Once an alarm state is detected a query is made as to the number or quantity of alarms  325 ,  335  detected. If multiple alarms  330  are detected, then a general alarm  335  is sounded via all devices in the fire alarm system  100 . If only one alarm  325  is detected, then its sole address/location is determined  340  via the stored physical address within the control system. Once the physical address/location  345  is known, an assigned sequence number  350  is placed on the audible, visible device. A activate command is sent to such audible devices  140  and visible devices  130  based on the assigned sequence number in order to direct the safest egress from the emergency situation relative to a “hot zone” which may constitute for example, a fire or other dangerous event. 
   Although an example of the fire alarm system  100  is shown using fire detection devices, it will be appreciated that other detection schemes can be used. Also, although the fire alarm system  100  is useful to direct the egress from any potentially dangerous/hazardous location, it can also be used to detect poisonous gases and/or hazardous atmospheres due to biological agents and the like and to direct the egress to safety. 
   The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.