US450466A - Fire-alarm and telephone system - Google Patents

Fire-alarm and telephone system Download PDF

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US450466A
US450466A US450466DA US450466A US 450466 A US450466 A US 450466A US 450466D A US450466D A US 450466DA US 450466 A US450466 A US 450466A
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telephone
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alarm
spring
wire
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    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B17/00Fire alarms; Alarms responsive to explosion
    • G08B17/06Electric actuation of the alarm, e.g. using a thermally-operated switch

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  • My improvements relate to a combination of fire-alarm and telephone system whereby an alarm of fire may be automatically communie-ated to the telephone exchange Without in any way altering said telephone system or affecting the ordinary telephonie intercommunication between the telephone exchange or station and the subscribers and users.
  • My invention is intended to utilize the ordinary telephone systems in use throughout the country by automatically looping onto the telephone-line wire upon an outbreak otv fire a magneto-electric generator with mechanism to operate the same and system of switches and circuits mechanically and automatically operated in connection with the subscribers telephonie transmitter, so that upon a re occurring the train of mechanism may be set in action, a call sent to the exchange in the usual way, the subscriber-s telephonic transmitter switched into the circuit, and a signal agreed upon, such as the ring- ⁇ ing of a bell, conveyed audibly to the operator at the exchange.
  • a signal agreed upon such as the ring- ⁇ ing of a bell
  • FIG. 1 is a diagram of various circuits.
  • Fig. Gis a perspective View showing the spring-connections, the working parts of the apparatus being removed.
  • Fig. 7 is a horizontal cross-section of the portion of the box shownin Fig. G.-
  • A is a suitable box to hold the workin g parts with a hinged door or lid B.
  • the binding-posts a, b, c, d, e, f, g, and h from which posts the Various external connections are made. From post a connection is made with the telephone line-wire and from post b to the telephone apparatus,.so that when posts d and b are in electrical connection within the box the'circuit is from the exchange into the box at post a and out again at postband to the subscribers telephone, andthis is the normal condition when the fire-alarm apparatus is not in operation.
  • From posts c and d connection is made by separate wires to the opposite ends of the primary coil of the microphone, and from posts c and g by separate wires to the opposite ends of the microphone inductioncoil of the telephone apparatus of the subscriber, so thatwhen postscand d are in electrical connection within the box and electrical connection is made within the box between posts a and e and between posts b and g a circuit will be established through the primary coil of the transmitter wit-h the microphone-battery,and another circuit will be established from the exchange through post a to post c, to secondary coil of transmitter, to post g, to post ZJ, and to the telephone-instruments.
  • C C are a pair of horseshoe-magnets
  • D the armature of same, the armature and its shaft E being driven by the gear-wheel F on shaft G, which meshes with the pinion II on the armature-shaft.
  • the armature D is incased in the usual metallic box K, which is supported on legs ⁇ it' to the bottom of the case, the armature-shaft being journaled in On top of the box K the standards L L and collars M M are secured, and in these collars the shaft G is journaled.
  • the shaft G is operated by a coiled spring N, a ratchet-wheel 7c, and dog l, holding the spring when wound up, while the wheel O, rigidly attached to the shaft with dog m, engaging a tooth therein, prevents the shaft G from revolving until the dog m is released, as hereinafter described.
  • the spring is wound up by a suitable key tting over the end of the shaft G, which extends without the box.
  • This arm and ball are held up by the armatures of the electro-magnet T, the arm being slightly out of the perpendicular, so as to rest against the end of the armature.
  • the arm is prevented from falling in the other direction by the stop t.
  • the wheel O having one notch u therein, is rigidly attached to shaft G, and within this notch u the dog m catches to hold same from being revolved by the action of the spring N; but when a current is passed through the coil of electromagnet T the armature will be attracted, release the arm S, and allow the ball r to fall, and the lower end of the arm S will strike the projection t* on dog fm, and release the whe'el O, thus allowing the shaft G to revolve under the action of spring N.
  • the thermostatwires from the posts f and 7L are electrically connected by wires 9 and 10 with the springs cc, secured to the back of the box, which extends out in front of the springs a. l2 and at right angles to said springs, these springs c c being connected together by hard rubber or other non-cond uctor.
  • the electro-magnet coil is in electric connection with the springs d d', secured to the side of the box with their ends bent at right angles, so as to come in contact with the thermostat-springs c c when the device is not in operation. In this way the thermostat is always in connection with the electro-magnet T. As soon, however, as
  • the springs e and g are in electrical connection by wires 3 and 4 with posts c and d, which are in connection with the primary coil of the subscribers microphone, so that when the ball r is down a circuit will be established with subscribers microphone-battery, while the circuit from spring f to support- U will be broken.
  • the coil of the armature D of the generator is in connection at one end with the metallic box K and at the other with insulated point o, which point is in connection by spring l with support U and Wire 2.
  • On the metallic nut R are the pins m m', and when the nut IOC IIO
  • the nut R After a certain number of revolutions, however, the nut R will be carried so far over as to break the connections between it and the springs n and o", and further revolutions of the armature D will have no effect on the transfer of sound over the telephone-wires.
  • the springs 0 r' Directly opposite to the springs n oon the other side of the nut R are the springs 0 r', one of which is in connection by wire G with post e and the other by wire 8 with wire 2, and as soon as the nut has traveled far enough to break connect-ion between the pins m m and spring ⁇ n the springs r 7" come in contact with said pins 'm/ m.
  • Another springp in connection with binding-post g by wire 7, is arranged so that when connection is broken between n and the nut R the springp will come into connection with 'n'. Therefore as soon as the nut R has traveled from one end of the collar I to the other a complete circuit will be established from the exchange through wires l and 5, spring n', spring p', post g to the secondary coil of subscribers microphone, back to post e, wire 6, one spring 0 ⁇ ',nut R, other springr, wire 8, wire 2 to telephone, and thence to ground, as all the circuits to the telephone will be when the instruments are not in use.
  • the combination with the telephoneline wire and telephone apparatus and electrical means for sending a call to the exchange independent of the telephone-instruments, of electrical circuits from the primary and secondary coils of the subseribers transmitter independent vof the ordinary telephone-eircuits of the telephoneapparatus, switches to close said circuits, and means for operating them automatically after a call has been sent, so that the telephone-transmitter may be placed in circuit independentof the telephonecircuits ofthe ordinary telephone apparatus to convey a sound to the exchange, substantially as shown and described.
  • a telephone-line Wire an independent magneto-electric generator in connection therewith, and circuits and switches in connectiontherewithforthrowingthesubscribers telephone-transmitter in circuit independent of the ordinary transmitter circuits -with mechanism for operating said generator and switches, in combination with fire-alarm apparatus and means for setting said mechanism in operation upon the outbreak of tire, and an electric bell in connection with the fire-alarm apparatus, substantially as shown and described.
  • thermostaneircuit swing hetWeen the open terminals ot ⁇ the electromagnet coil and the electric-bell coil, said thermostat-terminals being in eenneetion with the electro-magnet until the circuit is completed through the therniostaawhen their connection is automatically broken and made with the electric bell, substantially as shown and described.

Description

(No Model.) 4 Sheets-Sheet 1.'.
s. W. LUDLO'W.v PIRE ALARM AND TELEPHONE SYSTEM.
No. 450,466. Patented Apr. 14,' 1891.
. (No Model.) 4 sheets-Sheena.
S. W. LUDLOW. l PIRE ALARM AND TELEPHONE SYSTEM.
No. 450,466. Patented Apr. 14, 1891.
rn: noms Pneus co., mammie.. msnmawn, o, c,
(N0 Model.) 4 Sheets-Sheet 3.
V S. W. LUDLOW.
FIRE ALARM AND TELBPHUNE SYSTEM.
No. 450,466. I PatentedApr. V14, 1891.
LIL.
wzeavw.
(No Model.)
4 Shee-ts-Sheet 4. S. W. LUDLOW. FIRE ALARM AND TELEPHONE SYSTEM. No. 450,466.
Patented Apr. 14', 1891.
` UNITED STATES f PATENT OFFICE.
SAMUEL iV. LUDLO\V, OF MADISONVILLE, OHIO.
FIRE-ALARM AND TELEPHONE SYSTEM.
SPECIFICATION forming part of Letters Patent No. 450,466, dated April 14, 1891.
Application tiled October 25, 1390. Serial No.369.306 (No model.)
To cir/ZZ whom, it 771,603/ concern:
Be it known that I, SAMUEL lV. LUDLOW, a citizen of the United States, residing' at Madisonville, in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in Fire-Alarm and Telephone Systems, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings,
forming part ot' this speciii'cation.
My improvements relate to a combination of fire-alarm and telephone system whereby an alarm of fire may be automatically communie-ated to the telephone exchange Without in any way altering said telephone system or affecting the ordinary telephonie intercommunication between the telephone exchange or station and the subscribers and users.
My invention is intended to utilize the ordinary telephone systems in use throughout the country by automatically looping onto the telephone-line wire upon an outbreak otv fire a magneto-electric generator with mechanism to operate the same and system of switches and circuits mechanically and automatically operated in connection with the subscribers telephonie transmitter, so that upon a re occurring the train of mechanism may be set in action, a call sent to the exchange in the usual way, the subscriber-s telephonic transmitter switched into the circuit, and a signal agreed upon, such as the ring- `ing of a bell, conveyed audibly to the operator at the exchange. I accomplish this result by new and improved construction and arrangement of parts, which will hereinafter be more particularly pointed out and claimed.
Any of the well-known forms of thermostats or devices for determining the presence of fire may be used without departing from the spirit of my invention, which in the main vconsists of mechanism to be set in operation operation, the ordinary use of the telephone- In the drawings, Figure l is ay front view of the box containing my device with the-lid opened and the mechanism in place for sending' the call to the exchange and switching the various currents. Fig. 2 is the same view with the box and parts of thcmagneto electric generator in section. Fig. 3 is a crosssection taken on lines fr o: ot' Fig. 1, looking in the direction of the arrow. Fig. 4 isa side view of the apparatus, the side of the box heilig removed. Fig. 5 is a diagram of various circuits. Fig. Gis a perspective View showing the spring-connections, the working parts of the apparatus being removed. Fig. 7 is a horizontal cross-section of the portion of the box shownin Fig. G.-
Ais a suitable box to hold the workin g parts with a hinged door or lid B. At the top and bottom of this box are the binding-posts a, b, c, d, e, f, g, and h, from which posts the Various external connections are made. From post a connection is made with the telephone line-wire and from post b to the telephone apparatus,.so that when posts d and b are in electrical connection within the box the'circuit is from the exchange into the box at post a and out again at postband to the subscribers telephone, andthis is the normal condition when the fire-alarm apparatus is not in operation. From posts c and d connection is made by separate wires to the opposite ends of the primary coil of the microphone, and from posts c and g by separate wires to the opposite ends of the microphone inductioncoil of the telephone apparatus of the subscriber, so thatwhen postscand d are in electrical connection within the box and electrical connection is made within the box between posts a and e and between posts b and g a circuit will be established through the primary coil of the transmitter wit-h the microphone-battery,and another circuit will be established from the exchange through post a to post c, to secondary coil of transmitter, to post g, to post ZJ, and to the telephone-instruments. From posts f and h connection is made to the thermostats a and thermostat- ICO battery D, as shown in diagram, Fig. 5, by wires c and d, so that when the circuit is completed through the thermostat by the action of heat the train of mechanism within the box may be set in operation to make the various connections and to set in action the bell or other signal, the sound of which is to be conveyed to the exchange.
C C are a pair of horseshoe-magnets, and D the armature of same, the armature and its shaft E being driven by the gear-wheel F on shaft G, which meshes with the pinion II on the armature-shaft. The armature D is incased in the usual metallic box K, which is supported on legs `it' to the bottom of the case, the armature-shaft being journaled in On top of the box K the standards L L and collars M M are secured, and in these collars the shaft G is journaled. The shaft G is operated by a coiled spring N, a ratchet-wheel 7c, and dog l, holding the spring when wound up, while the wheel O, rigidly attached to the shaft with dog m, engaging a tooth therein, prevents the shaft G from revolving until the dog m is released, as hereinafter described. The spring is wound up by a suitable key tting over the end of the shaft G, which extends without the box.
Between the collars H M, on which the shaft G is journaled, is a screw-threaded collar P, keyed thereto so as to revolve with the same. Upon this collar P a threaded nut or collar R rides, which is prevented from revolving` with the collar P by a pin n, which slides in a slotp in the cross-bar o between the stand ards L L. It will be manifest from this arrangement that as the shaft G revolves the nut R will have a positive movement from one end of the collarP to the other. Loosely turning on shaft G is the arm S, carrying at its upper end a weighted ball fr. This arm and ball are held up by the armatures of the electro-magnet T, the arm being slightly out of the perpendicular, so as to rest against the end of the armature. The arm is prevented from falling in the other direction by the stop t. The wheel O, having one notch u therein, is rigidly attached to shaft G, and within this notch u the dog m catches to hold same from being revolved by the action of the spring N; but when a current is passed through the coil of electromagnet T the armature will be attracted, release the arm S, and allow the ball r to fall, and the lower end of the arm S will strike the projection t* on dog fm, and release the whe'el O, thus allowing the shaft G to revolve under the action of spring N. After the arm S and ball r have fallen far enough to release the dog m they are caught on the support U and prevented from rebounding by the catch w. Upon the outside of the box is an electric bell, as shown by the dotted lines in Fig. 1. One end of the coil of this bell is connected by metallic strips with the spring a by wire 12 and the other end with spring b by wire 13. The location of this electric bell is not material, so long as it is in the neighborhood of the subscriber-s telephone, so that its ringing may be heard at the exchange, and it is shown here on the outside of the box. holding the other parts of the apparatus merely for convenience. The best position for this bell would probably be immediately above or alongside of the subscribers transmitter, but so as not to interfere with the ordinary use of the telephone. The thermostatwires from the posts f and 7L are electrically connected by wires 9 and 10 with the springs cc, secured to the back of the box, which extends out in front of the springs a. l2 and at right angles to said springs, these springs c c being connected together by hard rubber or other non-cond uctor. The electro-magnet coil is in electric connection with the springs d d', secured to the side of the box with their ends bent at right angles, so as to come in contact with the thermostat-springs c c when the device is not in operation. In this way the thermostat is always in connection with the electro-magnet T. As soon, however, as
the circuit is completed through the thermostat by the action of heat the armature s of thc magnet is attracted, which allows the ball r to drop, and the lower end of the arm S, coming in contact with the dog m, drives it back against the springs c c', which breaks the connection between the thermostat-wires and the electro-magnet T and makes connection between the thermostat-springs and the bellsprings, and as long as the circuit is com plete through the thermostat the bell will continue to ring. Three springs e,f, and g', separate from each other, are located at the side of the box,the center onef being in connection with the metallic support U when the ball r is up, and one of the others, asg. havingabridge h coming out in front of the other e. l/Vhen the ball r has fallen,the knobs shown thereon in the drawings being insulating material, the connection between spring f and support U is broken, and by means of the bridge h' the three springs are brought into electrical connection. The wire from the exchange to post a is in electrical connection by suitable metallic strips in Fig. 5, wire l, with the spring f', `and the wire to the telephone from post l) is connected by wire 2 with support U, so that while the ball fr' is up the circuit from the eX- change to the telephone is into the box at post ct, to spring f', to U, to post h, and to telephone. The springs e and g are in electrical connection by wires 3 and 4 with posts c and d, which are in connection with the primary coil of the subscribers microphone, so that when the ball r is down a circuit will be established with subscribers microphone-battery, while the circuit from spring f to support- U will be broken.
The coil of the armature D of the generator is in connection at one end with the metallic box K and at the other with insulated point o, which point is in connection by spring l with support U and Wire 2. On the metallic nut R are the pins m m', and when the nut IOC IIO
IIK
R is at one end of the collar P the spring n is in connection therewith, the spring n is insulated from the box K, and the nut itself is in electrical connection with box K. Looped into wire l is the wire 5, through which con nection is made with spring n', and in this way as soon as the direct connection is broken between wires l and 2 by the fall of the ball o a circuit is made from the exchange throughwires l and 5, spring n', nut R, box K, armature-coil', spring' l', support U, and wire 2 to the telephone, and thus the revolution of the armature D will generate a current which will drop the subscribers annunciator-button at the exchange. After a certain number of revolutions, however, the nut R will be carried so far over as to break the connections between it and the springs n and o", and further revolutions of the armature D will have no effect on the transfer of sound over the telephone-wires. Directly opposite to the springs n oon the other side of the nut R are the springs 0 r', one of which is in connection by wire G with post e and the other by wire 8 with wire 2, and as soon as the nut has traveled far enough to break connect-ion between the pins m m and spring` n the springs r 7" come in contact with said pins 'm/ m. Another springp, in connection with binding-post g by wire 7, is arranged so that when connection is broken between n and the nut R the springp will come into connection with 'n'. Therefore as soon as the nut R has traveled from one end of the collar I to the other a complete circuit will be established from the exchange through wires l and 5, spring n', spring p', post g to the secondary coil of subscribers microphone, back to post e, wire 6, one spring 0^',nut R, other springr, wire 8, wire 2 to telephone, and thence to ground, as all the circuits to the telephone will be when the instruments are not in use.
The operation of my device will, I take it, be manifest from the above description. Having established throughout the building to be protected from ire the desired number of thermostats, arranged in connection with a battery to establish a circuit when a suficient degree of heat has been reached, the proper wire-connections can then be made with the binding-posts on subscribers telephone, as above described, the coiled spring N being wound up, the ball fr raised and held up by armature s, and the device is ready to send in an alarm of fire. The subscribers telephone can be used without being affected in any way, the circuit being complete 'from the exchange to the telephone through spring f and support U. As soon, however, as a current is established through the thermostat the ball r will be released, the dog m will be released from the wheel O, allowing the shaft G, and with it armature D, to revolve, a call will be sent to the exchange, the nut R will travel on the colllar P, connection will be made with the microphone, and the thermostat will ring continuously the electric bell placed in the neighborhood of the microphone, and the sound will be conveyed through the transmitter to the exchange.
I have shown in my device an electro-mag net to drop the ball which sets in operation the mechanism shown, and also an electric bell to make the signal of tire; but it is obvious that the ball may be dropped or the dog which holds the mechanism released by any well-known mechanical means, and that any of the well-known mechanical devices for determining the presence of heat may be employed for that purpose, and that it is not necessary that a bell should be used, but a whistle or rattle or otherinstrument to make a continuous noise could be adopted.
I am aware that it has been proposed hitlierto to connect the-telephone exchange with fire alarm apparatus; but all arrangements hitherto devised either require the employment of a separate system of wires to the exchange or require modiication to be made at the telephone exchange which would necessitate changes in the ordinary telephone system, while my device is distinguishable from all earlier devices of a like nature, in that no change whateveris required in the telephone system as ordinarily used, nor does the connection of my fire-alarm apparatus with the telephone in any way affect the ordinary use of the telephone.
Having thus fully described my invention, what I claim, and desire to secure by Letters Patent, is-
l. In a combined fire-alarm and telephone system, the combination, with the telephoneline wire and telephone apparatus and electrical means for sending a call to the exchange independent of the telephone-instruments, of electrical circuits from the primary and secondary coils of the subseribers transmitter independent vof the ordinary telephone-eircuits of the telephoneapparatus, switches to close said circuits, and means for operating them automatically after a call has been sent, so that the telephone-transmitter may be placed in circuit independentof the telephonecircuits ofthe ordinary telephone apparatus to convey a sound to the exchange, substantially as shown and described.
2. In a combined tire-alarm and telephone system, a telephone-line Wire, an independent magneto-electric generator in connection therewith, and circuits and switches in connectiontherewithforthrowingthesubscribers telephone-transmitter in circuit independent of the ordinary transmitter circuits -with mechanism for operating said generator and switches, in combination with fire-alarm apparatus and means for setting said mechanism in operation upon the outbreak of tire, and an electric bell in connection with the fire-alarm apparatus, substantially as shown and described. p
3. In a tire-alarm and telephone apparatus, the combination of thermostat and battery, electro-magnet and electric bell, wires in con- IOO nection therewith so arranged that the open terminals of the thermostaneircuit swing hetWeen the open terminals ot` the electromagnet coil and the electric-bell coil, said thermostat-terminals being in eenneetion with the electro-magnet until the circuit is completed through the therniostaawhen their connection is automatically broken and made with the electric bell, substantially as shown and described.
i. In a firealarm and telephone apparatus, i thecombinatiomwith thermostat and battery, of an electro-magnet T, armature s, the weighted arm S, held up thereby, and an electric bell with springs a b', c ef, and tl d', with the cir cuits described, so that the passage ot' an elec tric current through the electro-magnet will release the arm S and allow it to switch the thermostat-current from the electro-magnet to the bell, substantially7 as shown and dei scribed.
5. In a tire-alarm and telephone apparatus, the combination, with the telephone-line wire, of wires l and 2, forming a loop therewith, Wire 5,conneeting said wires l and 2 through the armature-coil of a magneto-electric gcncrator, shaft to operate same, and weighted arm S, released by the action et heat, which l on falling breaks connection between wires t l and 2 and allowsa circuit to be established t with the exchange through the said general tor, substantially as shown and described.
t3. In a fire-alarm and telephone apparatus, l the combination of the shalt G, threaded collar thereon with nut arranged to have a l positive movement along said shaft, with spring a in electric connection with wire l, spring p in electric connection with the transmitter induction-coil, and springs r r', one in connection with tral'ismitter inductioncoil and the other with Wire 2, said springs arranged, as described, so that as the nut moves with the revolution of the shaft the generator armature may be thrown out of circuit. and a complete circuit made with the exchange through the induction-coil of subscribers transmitter, substantially as shown and described.
i'. in a tire-alarm and telephone apparatus, the combination of magneto-electric generator with shaft to operate same driven by a spring, wheel O, and dog m, holding same7 weighted arm S, dropped bythe action et' fire and arranged to release said dog and allow the shaft to Operate springs e' g in connection with the primary coil of subscribers transmitter and brought in contact by the falling of arm S, nut R, moving with the revolutions ol' shaft G and in connection with the armature-coil of the generator, and springs ai p r r with electrieeonnections, as described, so that upon the dropping et the arm S a call will be sent tothe exchange and thereupon the subseribers telephone-transmittcr automatically thrown into the circuit, substantially as shown and described.
SAMUEL XY, LDLOXV.
l, vitnesses:
lnorten IEIDMAN, ALFRED M. ALLEN.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2516845A (en) * 1945-10-05 1950-08-01 Int Standard Electric Corp Telephone call-box system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2516845A (en) * 1945-10-05 1950-08-01 Int Standard Electric Corp Telephone call-box system

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