US669792A - Combined telephone and alarm system. - Google Patents

Combined telephone and alarm system. Download PDF

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US669792A
US669792A US2280100A US1900022801A US669792A US 669792 A US669792 A US 669792A US 2280100 A US2280100 A US 2280100A US 1900022801 A US1900022801 A US 1900022801A US 669792 A US669792 A US 669792A
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telephone
line
alarm
exchange
subscribers
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Angus S Hibbard
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M11/00Telephonic communication systems specially adapted for combination with other electrical systems
    • H04M11/04Telephonic communication systems specially adapted for combination with other electrical systems with alarm systems, e.g. fire, police or burglar alarm systems

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  • My invention relates to combined telephone and alarm systems, and has forone object the provision of means whereby the line-signaling instruments at telephone-exchanges may be employed to serve as alarm devices to indicate fires, burglars, or other alarms; and the invention has for its further object the provision of means wherebythe alarm indications may also be transmitted from the exchange to the alarm and registering office of a fire department or other alarm-station.
  • My invention is designed more particularly to produce an improved combined telephone and fire-alarm system, and I will hereinafter describe my invention more particularly as employed in connection with fire-alarm cir-- cuits, although I do not wish to be limited to this particular adaptation of the invention.
  • I employ telephone-lines having self-restoring line-signals at the exchange and associate with these lines suitable apparatus at subscribers stations responsive to fire which will serve, by means of suitable connections, to effect the actuation of the signals at the exchange, the apparatus being preferably such that a distinctive signal is impart-ed which will at once convey to the mind of the operator that the premises to which the corresponding telephone-line extends are on fire. The operator may then place the fire department in possession of information of the fire.
  • I employ a battery at the exchange included in normally open circuit with the telephone-line and acorresponding line-signaling instrument, the responsive apparatus, preferably a break-Wheel, at the subscribers station serving intermittently to close the circuit through the line-indicator to cause a characteristic fire-alarm signal.
  • the responsive apparatus preferably a break-Wheel
  • I provide suitable circuit connections and switch parts whereby when the breakwheelis set in operation that conductor which includes the telephone switch-hook and which is made and broken by the telephone switchhook is broken, so that even though the receiver be removed fromits hook this conductor is still incomplete, so that the break-wheel may always intermittently open and close the telephone-line,ineluding the common battery.
  • I also preferably associate a single signaling device common to a plurality of telephonelines, which device may be placed in the presence of a special operator, so that the signals may not only be manifested to the operator at a particular section of telephone-switchboard, but will also be manifested to a chief operator.
  • signals may be termed pilot'signals.
  • the signals that I prefer to employ as line and pilot signals are small incandescent lamps, whose fiashing will readily attract the operators attention.
  • a switch-hook is provided with two upper contacts, one of which is connected through a primary coil d to the remaining side e of the telephone-line, while the other upper contact constitutes a terminal of a branch including the telephone-receiverf and the secondary coil g, the said receiver and secondary coil being adapted for inclusion in a local circuit that also includes a condenser h when the switch-hook is elevated.
  • the condenser h serves to prevent the passage of current from the common battery at the exchange across the limbs of the telephone-line when the apparatus at the subscribers station-is not in use.
  • a magneto signal-bell 't' is connected in series with a condenser it across the limbs of the line. Any suitable form of apparatus responsive to fire may be employed at the subscribers station.
  • thermostatic devices 7c 76 which in the presence of fire are adapted, through suitable means, to release the pawl or detent I from engagement with a notch provided in the periphery of a. break-wheel m, as is well understood.
  • the limb c of the telephone-line includes the metallic portion of the breakwheel and a brush n, that normally rests upon a metallic pin carried by the metallic portion of the break-wheel.
  • the brush n is disconnected from its engaging pin, so that the telephone-switch is rendered incapable of closing the telephon eline, whereby manifestations of signals due to the break-wheel may not be interrupted upon the elevation of the switch-hook.
  • a break-wheel provided with three teeth and serving to complete the circuit through the telephone-line three times to each revolution of the wheel, the teeth as arranged serving toindicate thenumber 12.
  • a brush 0 is connected with the side 6 of the telephone-line and is adapted to make contact with the teeth of the break-wheel as the latter revolves.
  • a three-point switch 19 is illustrated for the purpose of testing the apparatus without elfec'ting the operation of the signals at the exchange. When the switchp is in the position illustrated, the line is in normal condition, and any operation of the firealarm apparatus at the substation will be accom panied by a propagation of fire-alarm signals to the exchange and fire-alarm station.
  • the switch 19 may be thrown into engagement wit-h its alternate contact when the desired tests may be effected without creating false alarms.
  • the limbs c e of the telephone-line terminate, respectively, in the short and long line-springs of a line spring-jack q and the armatures of a cut-off relay r, normally resting against contacts that serve to connect the common batterys across the limbs of the line.
  • the line-relay 75 constituting a line-indicator magnet, is normally included in circuit with the limbs e and c and the line-lamp 2f glows the pilot-relay is energized, this relay serving to close circuit through a pilot-lamp u, that may also be included in a local circuit having suitable resistance. It will thus be apparent that when the break-wheel is tripped through the action of fire a corresponding signal will be manifested by the line-lamp t, that will indicate to the operator the location of the fire, and the said signal will also be manifested at the pilot-lamp to indicate to an operator that a fire is at a subscribers station of one of a group of lines.
  • the switchboard operator may prevent more than one signal being manifested by the pilot-lamp by inserting suitable plugs Within the jacks of the re maining signaling-lines until the operator at thepilot-lampisproperlysignaled.
  • the magnet t and lamp i constitute one type of selfrestoring line-indicating means, while the magnet u and lamp it constitute one type of a self-restoring pilot-indicator.
  • the means illustrated may be employed.
  • a connecting-plug 1 provided with tip and sleeve contacts that constitute the terminals of a round circuit, including alarm or recording apparatus to w atthe firm-alarm station, and a battery :1", to effect their operation.
  • V 11 The combination with a group of telephone-lines extending from subscribers stations to an exchange, of alarm operating means provided at each of the subscribers stations in addition to the telephonic apparatus located thereat, a line-indicator at the exchange for each of said telephonelines, an indicator common to the said telephone-lines, alarm apparatus at an alarm-station, and an operators switching apparatus for excluding the said indicators and associating the said alarm apparatus with the telephone-line over which signals are being sent, substantially as described.

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Alarm Systems (AREA)

Description

No. 669,792. Patented Mar. l2, l90l.
- A. S. H-IBBARD.
COMBINED TELEPHONE AND ALARM SYSTEM.
(Application filed July 7,' 1900.)
(No Model.)
NITED STATES PATENT OFFicE;
ANGUS S. HIBBARD, OF CHICAGO, ILLINOIS.
COMBINED TELEPHONE AND ALARM SYSTEM.
SPEOIFIGATION formingpart of Letters Patent No. 669,792, dated March 12, 190i.
Application filed July 7, 1900. Serial No. 22,801. \No model.)
To all whom it may concern:
Be it known that I, ANGUS S. HIBBARD, a citizen of the United States, residing at Ohicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in a Combined Telephone and Alarm System, (Case No. 8,) of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing, forming a partof this specification.
My invention relates to combined telephone and alarm systems, and has forone object the provision of means whereby the line-signaling instruments at telephone-exchanges may be employed to serve as alarm devices to indicate fires, burglars, or other alarms; and the invention has for its further object the provision of means wherebythe alarm indications may also be transmitted from the exchange to the alarm and registering office of a fire department or other alarm-station.
My invention is designed more particularly to produce an improved combined telephone and fire-alarm system, and I will hereinafter describe my invention more particularly as employed in connection with fire-alarm cir-- cuits, although I do not wish to be limited to this particular adaptation of the invention.
In accordance with my invention I employ telephone-lines having self-restoring line-signals at the exchange and associate with these lines suitable apparatus at subscribers stations responsive to fire which will serve, by means of suitable connections, to effect the actuation of the signals at the exchange, the apparatus being preferably such that a distinctive signal is impart-ed which will at once convey to the mind of the operator that the premises to which the corresponding telephone-line extends are on fire. The operator may then place the fire department in possession of information of the fire. This may be accomplished by means of a suitable connect.- ing-plug having terminals constituting the ends of a circuit extending to thefire-alarm oflice, including thereat suitable alarm or illdicating apparatus, this plug by being inserted within the jack of the corresponding telephone-line then bringing the said alarm-circuit into circuit with the telephone-line to form a continuation thereof, so that the signals caused by the responsive apparatus at the corresponding subscribers station are manifested or recorded at the fire-alarm office.
In the preferred embodiment of my invention I employ a battery at the exchange included in normally open circuit with the telephone-line and acorresponding line-signaling instrument, the responsive apparatus, preferably a break-Wheel, at the subscribers station serving intermittently to close the circuit through the line-indicator to cause a characteristic fire-alarm signal. In order that the break-wheel at the subscribers station may be effective at all times in sending in fire-signals irrespective of the position of the switchhook, I provide suitable circuit connections and switch parts whereby when the breakwheelis set in operation that conductor which includes the telephone switch-hook and which is made and broken by the telephone switchhook is broken, so that even though the receiver be removed fromits hook this conductor is still incomplete, so that the break-wheel may always intermittently open and close the telephone-line,ineluding the common battery.
I also preferably associate a single signaling device common to a plurality of telephonelines, which device may be placed in the presence of a special operator, so that the signals may not only be manifested to the operator at a particular section of telephone-switchboard, but will also be manifested to a chief operator. Such signals may be termed pilot'signals. The signals that I prefer to employ as line and pilot signals are small incandescent lamps, whose fiashing will readily attract the operators attention.
I will explain my invention more fully by reference to the accompanying drawing illustrating one embodiment thereof as applied to telephone-exchange systems having lines terminating at relay-boards.
Lhave indicated but one telephone-line extendingtoasubscribersstationA. Atthisstation one type of telephonic apparatus is illustrated that may be employed; but it is to be understood that other forms of telephonic apparatus may be used ifdesired. I have illustrated a telephone-switch hook at, having permanent connection with one terminal of a transmitter 17, the other terminal of which is connected with one limb c of the telephoneline. A switch-hook is provided with two upper contacts, one of which is connected through a primary coil d to the remaining side e of the telephone-line, while the other upper contact constitutes a terminal of a branch including the telephone-receiverf and the secondary coil g, the said receiver and secondary coil being adapted for inclusion in a local circuit that also includes a condenser h when the switch-hook is elevated. The condenser h serves to prevent the passage of current from the common battery at the exchange across the limbs of the telephone-line when the apparatus at the subscribers station-is not in use. A magneto signal-bell 't' is connected in series with a condenser it across the limbs of the line. Any suitable form of apparatus responsive to fire may be employed at the subscribers station. I have illustrated thermostatic devices 7c 76, which in the presence of fire are adapted, through suitable means, to release the pawl or detent I from engagement with a notch provided in the periphery of a. break-wheel m, as is well understood. The limb c of the telephone-line includes the metallic portion of the breakwheel and a brush n, that normally rests upon a metallic pin carried by the metallic portion of the break-wheel. When the break-wheel is tripped, the brush n is disconnected from its engaging pin, so that the telephone-switch is rendered incapable of closing the telephon eline, whereby manifestations of signals due to the break-wheel may not be interrupted upon the elevation of the switch-hook.
I have illustrated a break-wheel provided with three teeth and serving to complete the circuit through the telephone-line three times to each revolution of the wheel, the teeth as arranged serving toindicate thenumber 12. A brush 0 is connected with the side 6 of the telephone-line and is adapted to make contact with the teeth of the break-wheel as the latter revolves. A three-point switch 19 is illustrated for the purpose of testing the apparatus without elfec'ting the operation of the signals at the exchange. When the switchp is in the position illustrated, the line is in normal condition, and any operation of the firealarm apparatus at the substation will be accom panied by a propagation of fire-alarm signals to the exchange and fire-alarm station. If it should be desired to test the operativeness of the fire alarm apparatus without causing the propagation of false-alarm signals over the line, the switch 19 may be thrown into engagement wit-h its alternate contact when the desired tests may be effected without creating false alarms. The limbs c e of the telephone-line terminate, respectively, in the short and long line-springs of a line spring-jack q and the armatures of a cut-off relay r, normally resting against contacts that serve to connect the common batterys across the limbs of the line. The line-relay 75, constituting a line-indicator magnet, is normally included in circuit with the limbs e and c and the line-lamp 2f glows the pilot-relay is energized, this relay serving to close circuit through a pilot-lamp u, that may also be included in a local circuit having suitable resistance. It will thus be apparent that when the break-wheel is tripped through the action of fire a corresponding signal will be manifested by the line-lamp t, that will indicate to the operator the location of the fire, and the said signal will also be manifested at the pilot-lamp to indicate to an operator that a fire is at a subscribers station of one of a group of lines. If it should happen that the pilot-lamp u is operated from two or more stations at the same time, the switchboard operator may prevent more than one signal being manifested by the pilot-lamp by inserting suitable plugs Within the jacks of the re maining signaling-lines until the operator at thepilot-lampisproperlysignaled. The magnet t and lamp i constitute one type of selfrestoring line-indicating means, while the magnet u and lamp it constitute one type of a self-restoring pilot-indicator.
Where it is desired to have the responsive apparatus at a subscribers station also act to operate alarm apparatus at a firm-alarm station, the means illustrated, among others, may be employed. For this purpose I have indicated a connecting-plug 1;, provided with tip and sleeve contacts that constitute the terminals of a round circuit, including alarm or recording apparatus to w atthe firm-alarm station, and a battery :1", to effect their operation. It is desirable when the fire -alarm station has thus been connected with the telephone-line to disconnect the signaling apparatus at the telephone-exchange, which may be efiect-ed by means of the grounded battery y, connected with the thimblecontact of the plug v, that serves to close circuit through the grounded cut-off relay 1' upon the insertion of the said plug, whereby the armatures of the said relay are attracted and the battery s and the line and pilot relays at the exchange are disconnected.
It will be observed that when the alarmoperating apparatus at the subscribers station is actuated a characteristic intermittent signal is manifested at the exchange, which indicates to the operator at once that an alarm-signal is being conveyed, so that the operator does not need to use her telephone to ascertain this fact.
I have herein shown and particularly described one embodiment of my invention; but
it is obvious that other embodiments thereof maybe made without departing from its spirit, and I do not therefore wish to be limited to the embodiment of my invention herein shown and particularly described; but,
Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1. The combination with a telephone-line extending from a subscribers telephone-station to an exchange, the said subscribers station being provided with a telephone switchhook adapted to close a branch between the sides of the telephone-line upon the removal of the receiver, of a signal at the exchange, means at the subscribers station responsive to fire for effecting the operation of the said signal, and means operated by said responsive means serving to open said branch associated with the telephone switch-hook to prevent this branch from being closed upon the removal of the receiver, whereby the said responsive means may act over the telephone-- line independently of the position of the switch-hook, substantially as described.
2. The combination with a telephone-line extending from a subscribers telephone-station to an exchange, the said subscribers station being provided with a telephone switchhook adapted to close a branch between the sides of the telephone-line upon the removal of the receiver, of a signal at the exchange, alarm-operatin g means at the subscribers station for effecting the operation of the said signal, and means operated by said alarm-operating means serving to open said branch associated with the telephone switch-hook to prevent this branch from being closed upon the removal of the receiver, whereby the alarm-operating means may act over the telephone-line independently of the position of the switch-hook, substantially as described.
3. The combination with a plurality of telephone-lines extending from subscribers telephone-stations to an exchange, of a battery at the exchange common to the said telephonelines and adapted for inclusion in circuit therewith, self-restoring visual line-indicating means associated with each of the said telephone-lines independently of the operators switching apparatus and adapted to be operated by the said battery, alarm-operated means at each subscribers station, in addition to the subscribers telephone apparatus, serving to complete the circuit of said battery through the line and thereby effect the operation of the corresponding line-indicating means, and a second signaling means common to and normally operatively associated with the group of telephonelines, whereby the latter is also actuated upon the operation of the said alarm-operating means at any subscribers station without the intervention of the operator, substantially as described.
at. The combination with a plurality of telephone-lines extending from subscribers telephone-stations to an exchange, of a battery at the exchange common to the said telephonelines and adapted for inclusion in circuit therewith, self-restoring visual line-indicating means associated with each of the said telephone-lines independently of the operators switching apparatus and adapted to be operated by the said battery, alarm-operating means at each subscribers station, in addition to the subscribers telephone apparatus, serving to complete the circuit of said battery through the line and thereby effect the operation of the corresponding line-indicating means, a second signaling means common to and normally operatively associated with the group of telephone-lines, whereby the latter is also actuated upon the operation of the alarm-operating means at any subscribers station without the intervention of the operator, and an operators switching appliance for disconnecting the said indicating means from a signaling-line, substantially as described.
5. The combination with a telephone-line extending from a subscribers telephone-station to an exchange, of a battery at the exchange for inclusion in circuit with the said telephone-line, self-restoring visual line-indieating means at the exchange associated with the telephone-line independently of the operators switching apparatus, and adapted to be operated by the said battery, alarni-operating means at the subscribers station in addition to the subscribers telephonic apparatus for effecting the operation of the said lineindicating means,said alarm-operating means serving to intermittently actuate the line-indicating means to convey a characteristic alarm-signal, alarm apparatus located at an alarm-station distant from the telephone-exchange and adapted for operation by said alarm -operating means, and an operators switching appliance for disconnecting the line-indicating means from the telephone-line and associating the said alarm apparatus with the telephone-line, whereby the alarm apparatus may be operated without further disturbance of the line-indicating means, substantially as described.
6. The combination with a telephone-line extending from a subscribers telephone-eta tion to an exchange, of a source or" current for inclusion in the circuit with the said telephoneline, line-indicating means at the exchange associated with the telephone-line in- IIO erating means, and an operators switching appliance for disconnecting the line-indicating means from the telephone-line and associating the said alarm apparatus with the telephone-line, whereby the alarm apparatus may be operated without further disturbance of the line-indicating means, substantially as described.
7. The combination with a telephone-line extending from a subscribers telephone-station to an exchange, of a source of current for inclusion in circuit with the said telephone-line, line-indicating means at the exchange associated with the telephone-line independently of the operators switching apparatus and adapted to be operated by the said source of current, alarm-operating means at the subscribers station in addition to the subscribers telephonic apparatus for effecting the operation of the said line-indicating means, the said alarm-operating means serving to intermittently interrupt the circuit incl uding the line-indicating means to convey the characteristic signal, alarm apparatus located at an alarm-station distinct from the telephone-exchange and adapted for operation by said alarm-operating means, and an operators switching appliance for disconnecting the line-indicating means from the telephone-line and associating the said alarm apparatus with the telephone-line, whereby the alarm apparatus may be continued in its operation without a further disturbance of the visual lineindicating means, substantially as described.
8. The combination with a telephone-line extending from a subscribers telephone-stationto a line-jack at an exchange, of a selfrestoring indicator at the exchange associated with the telephone-line independently of the operators switching apparatus, alarm-operating means at the subscribers station, in addition to the telephonic apparatus located thereat, for operating the indicator, the said alarm-operating means serving to intermittently interrupt the circuit including the lineindicating means to convey the characteristic signal, a circuit including alarm apparatus located at an alarm-station, a switching appliance for connecting the alarm-circuit as a continuation of the telephone-line, and means whereby the switching appliance may disconnect the indicator at the exchange from the telephone-line, substantially as described.
9. The combination with a telephone-line extending from a subscribers telephone-station to a line-jack at an exchange, of a selfrestoring line-indicator at the exchange, a common battery also at the exchange, the magnet of the line-indicator and the battery being included in normal but separable continuations of the telephone line, a cut-off relay, a connecting-plug serving upon its insertion within the line-jack to energize the cut-cit relay and thereby disconnect the battery and line-indicator magnet from the telephone-line, alarm-operating means at the subscribers station in addition to the telephonic apparatus located thereat, serving to operate the line-indicator when connected with the telephone-line, the said alarm-operating means serving to intermittently interrupt the circuit including the line-indicating means to convey the characteristic signal, and an alarm at an alarm-station operated by the said alarm-operating means, the said connecting-plug serving to associate the alarm apparatus with the telephone'line, substantially as described.
10. The combination with a telephone-line extending from a subscribers telephone-station to a line-jack at an exchange, of a selfrestoring line-indicator at the exchange, a common battery also at the exchange, the magnet of the line-indicator and the battery being normally connected with the telephoneline, a cut-off relay, a connecting-plug serving upon its insertion in the line-jack to energize the cut-off relay and thereby disconnect the battery and line-indicator magnet from the telephone line, alarm operating means at the subscribers station in addition to the telephonic apparatus located thereat, serving to operate the line but connected with the telephone-line, the said alarm-operating means serving to intermittently interrupt the circuit including the line-indicating means to convey the characteristic signal, and an alarm at an alarm-station operated by the said alarm-operating means, the said conmeeting-plug serving to associate the alarm apparatus with the telephone-line, substantially as described.
V 11. The combination with a group of telephone-lines extending from subscribers stations to an exchange, of alarm operating means provided at each of the subscribers stations in addition to the telephonic apparatus located thereat, a line-indicator at the exchange for each of said telephonelines, an indicator common to the said telephone-lines, alarm apparatus at an alarm-station, and an operators switching apparatus for excluding the said indicators and associating the said alarm apparatus with the telephone-line over which signals are being sent, substantially as described.
12. The combination with a group of telephone-lines extending from subscribers stations to an exchange, of alarm operating means provided at each of the subscribers stations in addition to the telephonic apparatus located thereat, an indicator common to the said telephone-lines, alarm apparatus at an alarm-station, and an operators switching apparatus for excluding the said indicator and associating the said alarm apparatus with the telephone-line over which signals are being sent, substantially as described.
13. The combination with a group of telephone-lines extending from subscribers stations to an exchange, of alarm operating means provided at each of the subscribers telephone-line over which signals are being I0 stations in addition to the telephonic appasent, substantially as described.
ratus located thereat, an indicator common to In Witness whereof I hereunto subscribe my the said telephone-lines, said alarm-operatname this 3d day of July, A. D. 1900.
ing means serving to intermittently actuate said indicator, alarm apparatus at an alarm- ANGUS HIBBARD station, and an operators switching appara- Witnesses:
tus for excluding the said indicator and as- GEO. S. IREDELL,
sociating the said alarm apparatus with the DANIEL E, GOE.
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