Voice-override alarm system

• US 4,703,312 A
• Filed: 08/22/1986
• Issued: 10/27/1987
• Est. Priority Date: 08/22/1986
• Status: Expired due to Term

• Current Assignee: Signal Communications Corporation
• Original Assignee: AudioSone, Inc.
• Inventors: Berry, Robert W. III
• Primary Examiner(s): Crosland, Donnie L.
• Application Number:
  US06/899,153
• Time in Patent Office: 431 Days
• Field of Search: 340/506-513, 340/521, 340/531, 340/692, 340/693, 379/37-44, 379/49, 379/63, 379/80, 381/58, 381/59, 381/110
• US Class Current: 340/506
• CPC Class Codes: G08B 29/06 Monitoring of the line circuits, e.g. signalling of line faults

Abstract

An emergency alarm system incorporating both signal generation and voice annunciation capabilities, for installation in a building or other structure. The system includes a standard fire alarm control panel and one or more loud speakers, each speaker having a series blocking capacitor. The panel has conventional supervisory circuitry and sensing/alarm terminals connected therewith, adapted to indicate an alarm condition when conditions warrant, as by signals received on multiple sensor lines that also communicate with the panel. A signal generator and amplifier are arranged to drive the speakers, under alarm conditions. There is provided a circuit-failure indicator including an electrical switch and an electro-responsive actuator device connected with the signal generator. The electro-responsive actuator device, when energized by the signal generator, maintains the switch in a closed-circuit condition. An electrically conducting loop circuit is connected with the sensing/alarm terminals of the fire alarm control panel, the loop circuit involving the two speaker lines and a d.c. conducting shunt. The electrical switch is connected in series in the loop circuit whereby failure of either the signal generator or amplifier results in the open-circuiting of the switch, thereby distrubing the continuity of the loop circuit. By the above arrangement, breakage of either speaker line of the loop circuit, or open-circuiting of the electrical switch will result in activation of the sensing device of the fire alarm control panel, through solely its two sensing/alarm terminals, in order to indicate the existence of a trouble condition.

Claims

1. In an emergency alarm system having a speaker, a blocking capacitor connected in series with the speaker, and a fire alarm control panel including a pair of sensing terminals thereon, circuit-failure indicating means comprising in combination:

(a) a d. c. conducting shunt connected in parallel with the speaker and series blocking capacitor,

(b) electrical switching means,

(c) an electro-responsive actuator device for operating said switching means,

(d) a signal generator connected to said electro-responsive device to energize the same and normally maintain said electrical switching means in closed-circuit condition,

(e) an electrically conducting loop circuit connected with the sensing terminals of the fire alarm control panel, said loop circuit comprising two speaker lines for connection respectively with said speaker and series connected blocking capacitor paralleled by said d. c. conducting shunt,

(f) said switching means being connected in series in said loop circuit whereby failure of the signal generator to function will result in the switching means becoming open-circuited, thereby to break the continuity of the loop circuit,

(g) breakage of either speaker line of said loop circuit or opening-circuiting of said switching means activating the sensing device of the fire alarm control panel to indicate a trouble condition.

2. The invention as defined in claim 1, and further including:

(a) an interface module for connection to the sensing terminals of the control panel,

(b) said electrical switching means, electro-responsive actuator device, and signal generator being mounted in said module.

3. The invention as defined in claim 1, wherein:

(a) said switching means comprises a relay having normally closed contacts connected in series with said loop circuit,

(b) said electro-responsive actuator device comprising a magnetic coil on said relay, arranged to operate said contacts.

4. An interface module for use with an existing fire-alarm control panel, the control panel being of the type having means for supplying d. c. power to the module, and having a pair of electrical lines adapted to be connected to a pair of terminals on the module, said control panel lines applying d. c. voltage of one polarity when no alarm condition exists, and applying d. c. voltage of the opposite polarity when an alarm condition exists, the module being adapted for driving at least one loud speaker, said module comprising in combination:

(a) signal generator means and an amplifier, said signal generator means being adapted to drive said amplifier,

(b) means responsive to application of said d. c. voltage of opposite polarity on said control panel lines, for connecting the output of the amplifier to drive the loud speaker, to thus provide an audible warning to personnel in the vicinity,

(c) a microphone capable of producing an input signal to said amplifier,

(d) means including a manually-operable switch for terminating the signal from the signal generator means, and for substituting therefor the signal produced by the microphone, whereby the signal from the latter takes precedence over that originating at the signal generator means, and

(e) visual indicator means controlled by said amplifier, providing a substantially constant visual reading of the output of the latter when the loud speaker is being driven by the signal generator means and amplifier, and for providing a flickering reading corresponding to voice fluctuations when the loud speaker is being driven by the signal from the mircophone and amplifier, whereby the said one indicator means can either verify the operativeness and signal level of the signal generator means or alternately function as a modulation indicator.

5. The invention as set forth in claim 4, wherein:

(a) said visual indicator means comprises a pair of light-emitting devices, and

(b) complementary switching means interposed between said amplifier and said light-emitting devices, for effecting illumination of one device when the other is off, and vice-versa, to provide redundancy for the one light-emitting device if the other inadvertently fails.

6. An interface module for use with an existing fire-alarm control panel, the control panel being of the type having means for supplying d. c. power to the module, and having a pair of electrical lines adapted to be connected to a pair of terminals on the module, said control panel lines applying d. c. voltage of one polarity when no alarm condition exists, and applying d. c. voltage of the opposite polarity when an alarm condition exists, said module containing an amplifier and being adapted for driving at least one loud speaker, and having a coupling transformer between the amplifier and the loud speaker, said module comprising in combination:

(a) signal generator means having an output connected to the amplifier and loud speaker, said signal generator means being adapted to produce a waveform falling in the audible range whereby an attention-attracting warning sound can be selectively provided to personnel in the vicinity of the loud speaker when an alarm condition exists, and

(b) automatic control means responsive to absence of an alarm condition, for altering the frequency of the signal generator means wherein sounds produced by vibrations in the core of the transformer are rendered less objectionable than would be the case were the frequency left unaltered.

7. The invention as set forth in claim 6, wherein:

(a) said control means alters the frequency by maintaining it substantially constant at a value below several hundred Hz.

8. An interface module for use with an existing fire-alarm control panel, the control panel being of the type having means for supplying nominal 115 volt a. c. power to the module, means for supplying d. c. power to the module, and having a pair of electrical lines adapted to be connected to a pair of terminals on the module, said control panel lines applying d. c. voltage of one polarity when no alarm condition exists, and applying d. c. voltage of the opposite polarity when an alarm condition exists, said control panel having a d. c. battery constituting a back-up source for said d. c. power supplying means and said d. c. voltage applying means, said module being adapted for driving at least one loud speaker, said module comprising in combination:

(a) signal generator means and an amplifier, said signal generator means being adapted to drive said amplifier,

(b) means responsive to application of said d. c. voltage of opposite plarity on said control panel lines, for connecting the output of the amplifier to drive the loud speaker, to thus provide an audible warning to personnel in the vicinity,

(c) switching means in said module, responsive to loss of 115 volt a. c. power to the module, for disconnecting said signal generator means and said amplifier from said d. c. power supplying means of the control panel, and preventing them from drawing current therefrom, so as to conserve energy supplied by said d. c. battery, and

(d) additional switching means, separate from said first switching means, and responsive to said reversal of d. c. voltage applied to said pair of terminals on the module, for reconnecting the signal generator means and amplifier to the d. c. power supplying means of the control panel, thereby enabling the interface module to operate for a limited time if an alarm condition arises while the 115 volt a. c. power is still absent.

9. An interface module for use with an existing fire-alarm control panel, the control panel being of the type having means for supplying nominal 115 volt a. c. power to the module, means for supplying d. c. power to the module, and having a pair of electrical lines adapted to be connected to a pair of terminals on the module, said control panel lines applying d. c. voltage of one polarity when no alarm condition exists, and applying d. c. voltage of the opposite polarity when an alarm condition exists, said control panel having a d. c. battery constituting a back-up source for said d. c. power supplying means and said d. c. voltage applying means, said module being adapted for driving at least one loud speaker, said module comprising in combination:

(a) a microphone and an amplifier, said microphone being adapted to drive said amplifier,

(b) means responsive to application of said d. c. voltage of opposite polarity on said control panel lines, for connecting the output of the amplifier to drive the loud speaker, to thus enable an audible verbal warning to be given to personnel in the vicinity,

(c) switching means in said module, responsive to loss of 115 volt a. c. power to the module, for disconnecting said amplifier from d. c. power supplying means of the control panel and preventing it from drawing current therefrom, so as to conserve energy being supplied by said d. c. battery, and

(d) additional switching means, separate from said first switching means, and responsive to operation of said microphone, for re-connecting the amplifier to the d. c. power supplying means of the control panel, thereby enabling the interface module to operate for a limited time as a public address system if an alarm condition arises while the 115 volt power is still absent.

10. An interface module for use with an existing fire-alarm control panel, the control panel being of the type having means for supplying d. c. power to the module, and having a pair of electrical lines adapted to be connected to a pair of terminals on the module, said control panel lines applying d. c. voltage of one polarity when no alarm condition exists, and applying d. c. voltage of the opposite polarity when an alarm condition exists, the module being adapted for driving at least one loud speaker, said module comprising in combination:

(a) signal generator means and an amplifier, said signal generator means being adapted to drive said amplifier,

(b) means responsive to application of said d. c. voltage of opposite polarity on said control panel lines, for connecting the output of the amplifier to drive the loud speaker, to thus provide an audible warning to personnel in the vicinity,

(c) a master microphone capable of producing an input signal to said amplifier,

(d) an auxiliary microphone capable of producing an input signal to said amplifier,

(e) means including a manually operable switch, for isolating the auxiliary microphone from the interface module at any time during which the an alarm condition arises and during which the signal generator means is driving the loud speaker, and

(f) means including a manually operable switch, for terminating the signal to the loud speaker from the signal generator means, and for substituting therefor any signal originating at the master microphone, whereby the signal from the latter takes precedence over that originating at the signal generator means.