Detecting, alerting and directing system
United States Patent 3916404

This is a system for the protection of personnel in an enclosed space. It comprises a danger detecting system such as a thermally operated electronic controller covering the area under protection, a distinctive audible alarm system which produces a recognizable sound or sound pattern audible throughout the area or enclosure to be protected, and visual directing means indicating the location of one or more exits and/or the direction in which a suitable exit lies. This visual directing system employs, preferably, a sign animated as by the flashing on and off of so-called strobe lights located at an exit, and the audible alarm signal is produced at the same exit. An auxiliary electric power supply system stands in reserve to take over the duty of providing electric power at any required time and, particularly, to be available for operating the detector circuits and the flashing light and warning sound circuits at low voltage from a storage battery which is constantly under recharge. The low voltage battery system can operate the protective and directing system for a reasonable time, such as 1 hour, in the event of failure of the commercial A.C. supply system.

Application Number:
Publication Date:
Filing Date:
Primary Class:
Other Classes:
40/570, 340/332, 340/815.53, 340/815.55
International Classes:
G08B7/06; G08B5/36; (IPC1-7): G08B7/00
Field of Search:
340/227,371,378,326,332,220 40
View Patent Images:
US Patent References:
2085807Signal system1937-07-06Lindsey

Primary Examiner:
Caldwell, John W.
Assistant Examiner:
Wannisky, William M.
Attorney, Agent or Firm:
Johnson, Dienner, Emrich & Wagner
Parent Case Data:


This application is a continuation of my copending application Ser. No. 130,890, filed Apr. 5, 1971 and now abandoned.
The invention claimed is

1. In a system of the class described for use with an enclosure having one or more exits for personnel, a detection system having sensors disposed throughout the enclosure, said sensors being responsive to the development of conditions deleterious to the occupants of the enclosure, a visual warning device comprising a housing having a front wall including a transparency adapted to be normally illuminated for continuously indicating the location of an exit, a lamp for illuminating said transparency, auditory alarm means activated by response of said sensors to said deleterious conditions to sound a distinctive warning signal audible throughout said enclosure warning the occupants to go to and out through an exit, means also activated by response of said sensors to cause flashing of said lamp, said visual device and said auditory alarm means being juxtaposed adjacent an exit whereby the occupants of the enclosure may be guided by sight and/or sound toward an exit.

2. For use in an alarm system for warning the occupants of an enclosure to vacate the same, an alarm signaling device comprising a housing adapted to be supported at the upper end of an exit from said enclosure, said housing having a front face comprising a transparency with warning characters which, when illuminated, indicate the presence of said exit, lighting means in said housing adapted to be illuminated to make said characters conspicuous, means for emitting a warning sound signal of loud and distinctive character, said sound emitting means being disposed in said housing and being arranged to emit said warning sound signal in the general direction towards which said warning characters are faced, and means responsive to predetermined conditions in said enclosure for illuminating said warning characters and for activating said auditory warning signal to give the occupant who receives either signal the direction in which the exit from the enclosure lies with respect to him.

3. An alarm system for use in connection with an enclosure having an exit, said system comprising a housing adapted to be mounted on the inside of the enclosure adjacent the upper end of the exit, said housing having a face with visual indications facing towards the inside of the enclosure, said housing face comprising a transparency including characters signifying the presence of an exit, and additional characters consisting of one or more arrows which when intermittently illuminated suggest motion toward the exit, an audible alarm device adapted to emit in a direction away from said exit a loud and distinctive warning sound said device being supported adjacent said illuminated indicators, and danger sensing means distributed throughout the enclosure to detect a condition for which evacuation is desirable, the illumination of said transparency and sounding of said audible alarm device being activated by response of said danger sensing means.

4. In a system of the class described for warning the occupants of an enclosure having an exit, to evacuate the same through said exit which comprises a detector circuit having sensors responsive to an inimical condition in the enclosure dispersed throughout the enclosure, an auditory warning device for producing a warning of loud and distinctive character, said device being located adjacent the exit and being audible throughout the enclosure, a visual exit indicator sign located adjacent the exit of the enclosure and adjacent to the auditory warning device and means activated by response of the detector circuit for causing the auditory warning to be sounded and said visual exit indicator sign to be flashed simultaneously, thereby providing the occupants of the enclosure with independently receivable auditory and visual indications of the direction in which the exit lies from an observer in the enclosure.


It is present practice that where persons are employed in an enclosed space, and fire, explosion, fumes, excessive heat or like dangerous condition arises, the occupants are directed by posted instructions to evacuate the enclosure. The various municipal state and other governmental codes prescribe the obligations of the management to provide warning and directions on what to do upon the occurrence of such dangerous conditions. But no matter to what extent personnel may be instructed by posted instructions, and short of frequent fire drills or the like, personnel does not become familiar with the location of the actually available exits, as they do with washrooms and the like with which they are familiar through usage.

I have observed the need for a system which will automatically detect danger and distinctly warn the occupants to evacuate the premises and will show them, and indicate by the direction from which a warning sound emanates, the nearest or most suitable exit, as well as the location of alternate exits, for use in case of congestion at a particular exit.


The system of the invention is adapted to protect personnel who occupy an enclosed space which may be a building or a part of the same, or an area with such restrictions upon exit as to constitute a threat to the safety of the occupants in the event that conditions arise which endanger health or safety.

Since the most usual situation requiring the protection which this system affords is a school, hospital, office building, factory, warehouse, foundry or the like, involving walls which house the operations or goods and enclose the workers or occupants, the need for an efficient protective system is widespread.

The invention involves means well distributed throughout the enclosure for detecting conditions which carry danger to the occupants. Since such conditions may arise almost anywhere in the enclosure and may develop suddenly, the detection system should have its sensors as widely distributed throughout the space as possible in order to respond promptly upon the occurrence of a dangerous condition. This is accomplished by sensors connected in parallel across a control circuit which promptly initiates an audible alarm of a distinctive character that may be heard throughout the enclosure. The visual and audible alarm producing means is preferably centrally located at one exit so that its warning may be heard throughout the enclosure, and persons going toward it will come into sight of a flashing EXIT sign. Optionally, a plurality of audible alarm warning devices may be disposed adjacent the exit signs. Alternatively, the alarm may be placed in each visual signal box or otherwise, according to any arrangement which will ensure wide spread audible warning that will be heard and recognized by the occupants so that in going toward the origin of the sound signal the occupant will be brought into sight of the flashing EXIT sign. The audible signal may be given by a horn which produces a pulsating sound. Also at this time the visual direction and location indicators are energized to direct the occupants to the exits and to apprise them of the actual location of one or more such exits. Where danger of congestion at some specific entrance or exit of the building might tend to occur, the direction signaling indicators may be so located as to divert personnel from particular areas to go towards specific exits even though the actual distance might be greater than the nearest exit. It is important that occurrence of a dangerous condition be detected as quickly as is feasible and that the entire personnel be alerted at once and directed out through the nearest available exit or exits.

The provision of an auxiliary self-charging battery power supply system assures the continued operation of the system for a considerable period of time after initial energization of the system.

The system has provision for testing and for connection with other systems. Signal circuits extending outside the confines of the partucular area for indicating a need for local or municipal fire departments may be provided. The system has a supervisory circuit which detects and gives visual alarm in case the sensing circuit has become defective or broken. This circuit is designated as a trouble alarm circuit. A small amber light on each unit stays lit until the trouble is corrected.

Where there is danger of the path to the exit, or the signals leading to them, being obscured or out of the direct line of vision, an illuminated direction indicator may be provided for providing local illumination and direction indication when the sensor circuit is energized.


FIG. 1 is a diagram of an installation of the system of the present invention;

FIG. 2 is a diagram of the power supply operational and testing circuits for location in a common boxlike container which serves also as an illuminated sign;

FIG. 3 is a diagram of a single unit system;

FIG. 4 is a perspective view of an illuminated exit sign;

FIG. 5 is a view of the exit sign disassembled; and

FIG. 6 is an illustration of an element of the sign showing an arrow in silhouette.


As indicated in FIG. 1, an enclosure having definite passageways or runways such as may be found in schools, hospitals, office buildings, factories, warehouses and the like, consisting in this case of the longitudinal passageway 1 terminates in an exit 2 (at the left of the figure) and extends to the right to a similar exit 3. This longitudinal passageway 1 is connected to a parallel passageway 4 which extends from an exit 5 to a junction at 6 with a transverse passageway 7. No exit is provided at the corner junction 6 but an exit 5 is provided at the left end of the passage.

The corridors or passageways which are indicated at 1, 4 and 7 may be considered as aisles or passageways in a single building or in a group of structures or in a common enclosure in which personnel is enclosed and may be performing various duties throughout the enclosure. In order to determine the conditions under which evacuation of the enclosures should be conducted and to bring about such evacuation requires, first, that there be means for detecting the condition or conditions which require such evacuation anywhere in the enclosure and, second, that all of the personnel in the enclosure be simultaneously notified that evacuation is to be effected immediately.

In an extensive enclosure with few exit doors or openings it is difficult for the occupants of the enclosure to decide which way to go as soon as the alarm is given for such evacuation of the premises.

The present system is designed to assist them in making the decision of which way to go to get to the nearest exit even though they be in a part of the enclosure with which they are not familiar and concerning which they may have no idea of the nearest exit.

As indicated in FIG. 1 the corridors 1, 4 and 7 are assumed to be typical corridors in an extensive office building, school, hospital, motel, warehouse, or factory complex. In order to determine the existence of conditions requiring evacuation of the building, I provide sensors which may be thermostatic switches bridged across a pair of conductors along the lines 8a leading to a sensing ralay. The heat sensitive sensors 8 are distributed throughout the occupied space so that if, for example, a fire should start somewhere nearby a heat sensor 8 would shortly be activated and close the circuit to the sensing relay 9 shown in FIG. 2. The two conductors 10 and 11 indicated in FIG. 2 include the winding of the relay 9 and the low voltage battery 12. The winding of the relay or electronic sensing circuit 9 is energized to close the relay contacts 13 whereby to close the local circuit which includes the pulsating audible signal 14 and the so-called strobe lights 15 and 16 through the automatic interrupter 17 which may lead a separate circuit to each of the lights 15 and 16 for the purpose of indicating a direction of motion on the exit indicator shown in FIGS. 4 and 5.

The pulsating audible signal 14 preferably emits a strong high-pitched sound. Any form of distinctive sound signal which can be heard all over the premises may be employed. This sound producing element is housed in the upper compartment 18 of the exit indicator fixture 19 of FIG. 4. Thereby the sound signal and the light signal come from the same location--namely, the immediate region of the exit. The occupant receiving either signal (or both signals) can unerringly proceed to the exit.

Said exit indicator fixture 19 has a supporting bracket 20 which may be mounted on a standard outlet box of an electrical distribution system. The arm 20 is connected to the top of the upper compartment 18 by screws so that the face of the sign may be turned on a horizontal plane in any direction.

The bottom of the fixture 19 comprises a wall 22 which is slotted or otherwise perforated. A transparent plastic plate overlies the openings 23 in the bottom wall 22 to emit light from the lamps contained in the fixture 19 as hereinafter explained. The body of the fixture 19 permits endwise insertion and removal of the masking plate or wall 24. This plate 24 had the word EXIT cut or stamped therethrough so that by location of a ruby glass or similarly colored plastic plate between the lamps in the central part of the fixture 19 and the plate 24, it will produce the illuminated word EXIT.

There are two end compartments in the fixture 19. These compartments 25, 26 each contain a separate lamp or, if desired, a larger number of lamps in each compartment back of the perforated opening 27 formed in the removable plate 28 adapted to cover the face of the ruby glass or red plastic plate overlying the end compartment at each side of the central compartment. In FIG. 5 I have illustrated the manner of assembly of the fixture 19, and in FIG. 6 I have indicated the removable and reversible character of the arrow indicating plate 28. The plates 28, 28 at each side of the central compartment carry the arrow perforation with a glass or plastic between the arrow shaped opening and the lamp, such as lamp 15 indicated in FIG. 5 which lies in each of the said end compartments.

The ability to change the direction indication of the arrow perforations 27 in the front of the side compartments permits information in regard to the proper direction for the viewer to pursue as is indicated, for example, in FIG. 1. In FIG. 1 three different direction signals are indicated. At locations 2, 3 and 5 the arrow indications may be replaced by imperforate sheets which blank off the end compartments or, under appropriate conditions, the arrow indications may point towards each other--that is, toward the center of the sign to indicate preference for the use of the immediately adjacent exit. At the location 6 on FIG. 1 the two arrows would be aligned in the same direction as in FIG. 4 of the drawings to indicate that the the left, as viewed in FIG. 4, is the proper direction to proceed towards the exit.

At location 30 in FIG. 1 the arrow indications 27, 27 would be pointed to the left and to the right, respectively, to indicate that either direction to an exit is available. Thus, at the location 30 as indicated in FIGS. 1 and 3, the arrow indications 27, 27 point in opposite directions to indicate that an exit is available either to the left at 2 in FIG. 1 or to the right at 3 in FIG. 1. If desired, the word EXIT may be blanked off and only the arrows 27, 27 (FIG. 6) illuminated intermittently pointing in opposite directions or preferably the word EXIT is illuminated along with the intermittenly illuminted arrow indications 27, 27.

The option to employ both visual and audible signals together provides a new capability in directing the occupants of the protected enclosure quickly and definitely to the outside of the enclosure through an available exit.

The sytem is basically new in giving simultaneously to an occupant of an enclosure two separate and distinct indications of the direction from his position to an exit through which he can escape. Hence impairment of either sight or hearing alone of an occupant of the endangered enclosure does not render him unable to receive the message to go to the indicated exit. My invention, by sending out both kinds of signals from the same point of origin--namely, the exit or its immediate vicinity--provides a new, unobvious and useful utility.

The circuit arrangement shown in FIG. 2 indicates the manner of maintaining a stand-by low voltage battery which is normally under recharge.

At the left of FIG. 2 the standard 110 Volt A.C. supply circuit 32 is connected to the transformer 33 which, in turn, is connected on its low voltage side to a solid state rectifier 34. It in turn is connected permanently to the battery 12 supplying current during the operation of the alarm circuit to the various lamps and to the pulsating audible signal 14.

A series of low voltage lamps 35 are mounted in the central compartment of the fixture 19 of FIG. 4 to illuminate the word EXIT continuously. These lamps are bridged across the rectifier 34 and consequently provide continuous illumination.

The botton wall of the fixture 19, as indicated at 23 in FIG. 4, has openings which may be covered by transparency for casting light down upon the door and threshold of the exit with which the sign is associated.

A single unit sign having a sensor circuit 8a when activated closes the relay circuits 13 in the low voltage alarm sensing circuit. This in turn activates the pulsating audible signal 14 and sets into operation the strobe lights 15, 16. Thereby the occupants of the enclosure who are out of sight of the exit sign may be guided by ear toward the exit. Then upon coming into view of the flashing lights of the exit sign, the occupant may proceed through the exit indicated.

The intermittent flashing of the arrow indications 27, 27 and the steady illumination of the exit sign are effective in directing personnel to the exit as soon as, or when, they are in view of the illuminated sign.

The system shown in FIG. 2 may pass information to a supervisory service as indicated at the right of FIG. 2 by the inductance and capacitance in the line extension to a monitoring service or the like. Provision is made through the test switch 38 shown in FIGURE to close the alarm sensing circuit for testing purposes or for emergency evacuation.

An emergency button or switch wired across 38 can be operated from a predetermined location such as a telephone switchboard, security office, or other supervised location for triggering the evacuating system in case of bomb threat, etc.

While the preferred form of the invention disclosed herein provides for location of the light emitting signal means and the sound emitting signaling means close together, in fact in the same housing, it is not essential that they be so closely mounted so long as they are associated closely enough to appear to indicate a definite association and to be regarded as indicating the same exit opening.

An advantage of the location of the housing 19 which contains the continuously lighted lamp or lamps in such position that light from the inside of the central compartment shines through the bottom openings 23 onto the threshold of the exit is that thereby compliance with the general safety requirements for continuous illumination of the of the doorway of a fire exit is effected.