US470666A - Police and fire-alarm signaling apparatus - Google Patents

Police and fire-alarm signaling apparatus Download PDF

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US470666A
US470666A US470666DA US470666A US 470666 A US470666 A US 470666A US 470666D A US470666D A US 470666DA US 470666 A US470666 A US 470666A
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    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B25/00Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems
    • G08B25/01Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems characterised by the transmission medium
    • G08B25/04Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems characterised by the transmission medium using a single signalling line, e.g. in a closed loop
    • G08B25/045Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems characterised by the transmission medium using a single signalling line, e.g. in a closed loop with sensing devices and central station in a closed loop, e.g. McCullough loop

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  • My invention relates to multiple signalboXes designed to send warning or emergency signals, and also the usual or customary police-signals.
  • the object of my invention is to provide a signal-box and central-office apparatus of a simple and efficient character, entirely automatic in its operation, and which will always operate with certainty to send warning or emergency signals, each box momentarily making its own earth connection at the instant of sending the Warning or emergency signal, such eart-h connection being immediately thereafter broken or removed, so that the use of any signal-boxes in the circuit will not be interfered with. It will be understood that it is of the utmost importance to the efficient Working of any police signaling system or apparatus that there be little or no uncertainty, that the emergency signal should be properly transmitted and received, and that the apparatus provides against every contingency for the failure of such signals in the hands of unskilled persons.
  • My invention consists, essentially, in a pol lice electric signaling system having the usual metallic circuit, including a battery and transmitting and receiving instruments, in combination with an earth-branch circuit at the signal-box or transmitting-instrument, which is adapted to be connected with the metallic circuit by the operation of the transmittinginstrument in sending the special or warning signal and then immediately disconnected, there being also another or second earthbranch circuit at the central oice, which is connected with the metallic circuit by the operation of a relay or magnet included in such metallic circuit whenever the latter is interrupted.
  • This second earth-branch circuit, or the one at the central office is furnished with an electro-magnet devicesuch as an annunciator-drop, for example-which operates when energized electrically to immediately open or disconnect this second earth-branch circuit.
  • each signal-box or transmitting-instrument operates momentarily to make its own earth connection at the instant of sending the special or warning signal, the same being at once broken thereafter and the earth connection at the central office being also broken or disconnected the instant the alarm-bell. or signal apparatus is set in operation,so that the metallic circuitand signaling apparatus are instantly restored and left in their normal condition free from earth connections immediatel y after the emergency signal is transmitted and received and before the signal-wheel begins to give the box-n u mber or other signal.
  • Figure 1 shows a side elevation of a signal box and apparatus or system of circuits embod yin g my invention.
  • Fig. 2 is a detail plan view of the circuit or signaling wheel.
  • Fig. 3 is a side elevation of, the same.
  • Fig. 4 is a detail perspective view of the device for making the ground connection at the signal-box when the signal is being sent and breaking it thereafter.
  • A represents a signal-box or transmitting-instrument of any ordinary or usual construction, which, with other like boxes or instruments, is connected in the main circuit B in the usual way.
  • C represents the receiving or registering instrument at the central station for receiving and registering the different signals.
  • the box A has the usual inner door A', which may be opened by the policeman withthe key provided for the purpose, upon which door is journaled or mounted the usual operating-leve'r or crank-shaft F, by which the signal- IOO Wheel G of the transmittinginstrument may be operated by a citizen to send special or warning signal Without opening this inner door.
  • the box is also vfurnished with the customary starting-lever or crankshaft H inside the door A,Which is designed to be operated solely by the officers or persons authorized to open this inner doorA, and who are furnished with keys for the meme-pose.
  • Vhen the operating-lever or crank-shaft F is moved to send a special or warning signal, its innerarm f engages the starting-lever H, and thus turns the sign al-wheel G of the transmitting-instrument.
  • B represents the battery for the main circuit B; B2, the relay or magnet for operating v the pencil or registering-lever c of the registering apparatus C, and by which, also, the earth branch D2 at the central station is closed when the metallic circuit B is interrupted.
  • D is the magnet for operating the annunciator-drop lever d, the same being included in the earth-branch circuit D2 at the central otiice
  • E is the magnet in the local circuit E2, operated by the local battery E2 for operating the alarm-bell E when the circuit E2 is closed by the annunciator-drop D.
  • earth branch D2 is closed at d2d2by the move ment of the armature-lever c Whenever the metallic circuit B is interrupted-thatis to say, opened or closed-opened it' it is arranged normally closed, or closed if it is arranged normally open.
  • the signal-Wheel of the transmitting-instrument is furnished with a series of signaling-teeth C, constructed in the usual Way to transmit any signals desired.
  • the signal-wheel G is also furnished with one tooth or cog g', which is longer or Wider than the other-sand extends, preferably, the full Width ot' the sigual-WheeLas is clearly indicated in Fig. 2.
  • K K are two contact pieces or springs secured to an insulating-support' K2, one ot which K forms part of the main circuit B.
  • the contact finger or spring K forms part of an earth-branch circuit 7c at the signal-box or transmitting-instrume'nt and leading to the earth at k through the movable contact-piece k2 and xed contact 7a2.
  • the movable contact-piece k2 is mounted to move or slide on the signal-box A or on the frame-Work of the l signaling apparatus, and it is adapted to be operated by an arm f', connected with the operating lever or hook F,Which is pulled down to send the special or Warning signal.
  • the movement ot ⁇ the operating-lever or crankshaft F rotates the signal-Wheel and at the same time actuates the sliding contact-piece 7a2 to close the earth-branch .circuit 7c, and thus connect the box withv the earth, so that when the si guai-Wheel Gis rotated suiiiciently to bring its long signal-tooth g under the contact-springs K K the signal-box Will be connected With the registering mechanism and annunciai'or-drop magnet at the central station.
  • the spring-contactK breaks' connection With the long tooth g and thus cuts out the earth branch k almost at the very instant that it is made.
  • the movable contact-piece 7a2 is also returned to place by the backward movement of the starting-lever H, which is returned by the main spring H of the transmitting-instrument,s0 that the earth connection is here broken to prevent the repetition kof the emergency signal and to prevent the earth connection interfering with other signals on the line when the signal-wheel is revolved from the inner lever H. It will be understood that to send the emergency signal through the main circuit B and annunciatorbranch circuit D2 only a momentary closing of the circuit is required, as a single impulse given to the annunciator-drop lever d Will release the drop D, close the alarm-circuit E2, and set the alarm-bell to ringing.
  • the annunciator branch circuit D2 has a ground connection at D2, and when the ground branch k is connected With the main circuit B by the movable contact k2 and by the long tooth g and spring contact-piece K it will be observed that the box is connected in a closed circuit with the annunciator-drop magnet D2, and the moment the annunciator-drop is released this earth circuit is broken at d5 and the alarm-circuit E2 closed by the movement of the drop D.
  • the ground branch c at the transmitting-instrument or signal-box, and also the ground branch D2 at the central ottice, it Will be observed, are by my invention both broken before the signal-wheel G begins to send the signals by the passage of the signaling-teeth g under the contact-spring K'.
  • the annunciator-drop branch D2 is preferably arranged normally open at cl2 d3, the movement of the registering-lever c closing this branch at cl2 d2 when the main circuit B is iirst opened or broken by the rotation ofthe signaling-Wheel.
  • the closing ot' the annunciator-drop branch may, however, be effected by the closing, instead of the breaking, ot' the main or metallic circuit B, according as such circuit is normally open or closed.
  • Opening the outer door A2 of box A discloses the hook or pull F, which when pulled down engages with the starting-lever Hand sliding ground-plate k2 inside of the inner door A', and thus rotates the circuit-Wheel G,Eig. 2, thereby opening the circuit B at K before the tooth4 g comes in contact with both fingers K K', and thus connecting the earth branch D2 at d2 d3 With the metallic circuit B by releasing the armature-lever c.
  • a police electrical signaling system the combination, with a metallic circuit having included therein a battery, a receiving or registering instrument, and a signal-box ,or transmitting-instrumenu of an earthbranch circuit at the signal-box or transmitting-instrument, a movable contact-piece included in said earth branch, means for operating said movable contact-piece to close said earth branch by the movement of the operating lever or hook of the signal-box, and a contact linger or spring operating, in conjunction with the signaling-Wheel of the boX, to connect and immediately disconnect said earth branch with said metallic circuit before the sending of the signal, so that said earthbranch connection may not interfere with the transmission ot' signals over the line by reason of said main line being connected with the ground, substantially as specified.
  • the Combination With a metallic circuit, including a battery and transmitting and receiving instruments, of arelayin the metallic circuit, operating' whenever the current in said circuit is interrupted to connect'said metallic circuit to earth through a branch, including an electro-magnetic annunciatordrop device,
  • a metallic circuit having included therein a battery, a receiving or registering instrument, and a signal-box or transmitting-instrument, of an earth-b ran ch circuit at the signal-box or transmitting-instrument, a movable contact-piece included in said earth branch, means for operating said movable contact-piece to close said earth branch by the movement of the operating lever or hook of the signal-box, and a contact finger or spring operating, in conjunction With the signaling-Wheel of the box, to connect and disconnect said earth branch With said metallic circuit, a second earth branch at the central office or receiving-instrument having included therein an annunciatordrop, said second earth branch being closed by a relay operating when the current is interrupted in said metallic circuit and then immediatelybroken or disconnected by the drop, substantially as specified.
  • the combination ot metallic circuit B having magnet B', battery B2, and signaling-Wheel G, furnished With signal-teeth g andv long tooth g l included therein, contact tingers or springs K K', earth-branch circuit k, having contactpiece 7c3 and movable contact-piece k2 included therein, starting-lever H, operating-V lever F, having arm j' engaging said lever H, and arm f engaging'said movable contactplate k2, earth branch Dhavingannunciatordrop D and magnet D included therein, and
  • armature-lever c operating to close said earth branch D2 at d2 d3, substantially as specified.
  • a metallic circuit having included ltherein a battery, a receiving-instrulnent, and a signal-box or transmitting-instruinent, of a ground branch at the signal-box, mechanism for connecting and immediately disconnecting said ground branch with said metallic circuit by the Operation of said transmitting-instrument prior to the transmission of the signal, and a second ground branch at the central oiiice or receivi11g-instrumenthaving included thereinan electro-magnetic annunciator-drop device for opening or disconnecting such ground branch the instant the same is electricallyv energized, the armaturelever of said receiving-instru ment at the first impulse thereof closing said ground branch at the central office, substantially as specified.

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  • Physics & Mathematics (AREA)
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  • Alarm Systems (AREA)

Description

`* NITED ASTATES 'PATENT OFFICE.
LEROY I5. FIRMAN, OF CHICAGO, ILLINOIS.
POLICE AND FIRE-ALARM SIGNALING APPARATUS.
SPECIFICATION forming part of Letters Patent No. 470,666, dated March 15, 1892. Application filed April 1, 1889. Serial No. 305,571. (No model.)
To 6l/ZZ whom, zit-may concern.-
Be it known that I, LEROY B. FIRMAN, a citizen of the United States, residing in Chicago, in the county of Cook `and State of Illinois, have invented a new and useful Improvement in Police and Fire-Alarm Signaling Apparatus, of which the following is a speciiication.
My invention relates to multiple signalboXes designed to send warning or emergency signals, and also the usual or customary police-signals.
The state of the art to which my invention relates is indicated by the system or apparatus shown and described in the patent to l/Vatkins, No. 172,219, dated January 1l, 1876.
The object of my invention is to provide a signal-box and central-office apparatus of a simple and efficient character, entirely automatic in its operation, and which will always operate with certainty to send warning or emergency signals, each box momentarily making its own earth connection at the instant of sending the Warning or emergency signal, such eart-h connection being immediately thereafter broken or removed, so that the use of any signal-boxes in the circuit will not be interfered with. It will be understood that it is of the utmost importance to the efficient Working of any police signaling system or apparatus that there be little or no uncertainty, that the emergency signal should be properly transmitted and received, and that the apparatus provides against every contingency for the failure of such signals in the hands of unskilled persons.
My invention consists, essentially, in a pol lice electric signaling system having the usual metallic circuit, including a battery and transmitting and receiving instruments, in combination with an earth-branch circuit at the signal-box or transmitting-instrument, which is adapted to be connected with the metallic circuit by the operation of the transmittinginstrument in sending the special or warning signal and then immediately disconnected, there being also another or second earthbranch circuit at the central oice, which is connected with the metallic circuit by the operation of a relay or magnet included in such metallic circuit whenever the latter is interrupted. This second earth-branch circuit, or the one at the central office, is furnished with an electro-magnet devicesuch as an annunciator-drop, for example-which operates when energized electrically to immediately open or disconnect this second earth-branch circuit. By this means each signal-box or transmitting-instrument operates momentarily to make its own earth connection at the instant of sending the special or warning signal, the same being at once broken thereafter and the earth connection at the central office being also broken or disconnected the instant the alarm-bell. or signal apparatus is set in operation,so that the metallic circuitand signaling apparatus are instantly restored and left in their normal condition free from earth connections immediatel y after the emergency signal is transmitted and received and before the signal-wheel begins to give the box-n u mber or other signal.
It also consists in the novel devices and novel combinationsot' parts and devices herein shown and described, and more particularly pointed out in the claims.
In the accompanying drawings, which form a part of this specification, and in which similar letters of reference indicate like parts, Figure 1 shows a side elevation of a signal box and apparatus or system of circuits embod yin g my invention. Fig. 2 is a detail plan view of the circuit or signaling wheel. Fig. 3 is a side elevation of, the same. Fig. 4 is a detail perspective view of the device for making the ground connection at the signal-box when the signal is being sent and breaking it thereafter.
In the drawings, A represents a signal-box or transmitting-instrument of any ordinary or usual construction, which, with other like boxes or instruments, is connected in the main circuit B in the usual way.
C represents the receiving or registering instrument at the central station for receiving and registering the different signals.
D is an annunciator-drop or its equivalent, and E an alarm bell or device to give the warning or emergency signal at the central station. The box A has the usual inner door A', which may be opened by the policeman withthe key provided for the purpose, upon which door is journaled or mounted the usual operating-leve'r or crank-shaft F, by which the signal- IOO Wheel G of the transmittinginstrument may be operated by a citizen to send special or warning signal Without opening this inner door. The box is also vfurnished with the customary starting-lever or crankshaft H inside the door A,Which is designed to be operated solely by the officers or persons authorized to open this inner doorA, and who are furnished with keys for the pui-pose. Vhen the operating-lever or crank-shaft F is moved to send a special or warning signal, its innerarm f engages the starting-lever H, and thus turns the sign al-wheel G of the transmitting-instrument.
B represents the battery for the main circuit B; B2, the relay or magnet for operating v the pencil or registering-lever c of the registering apparatus C, and by which, also, the earth branch D2 at the central station is closed when the metallic circuit B is interrupted.
D is the magnet for operating the annunciator-drop lever d, the same being included in the earth-branch circuit D2 at the central otiice, and E is the magnet in the local circuit E2, operated by the local battery E2 for operating the alarm-bell E when the circuit E2 is closed by the annunciator-drop D. The
earth branch D2 is closed at d2d2by the move ment of the armature-lever c Whenever the metallic circuit B is interrupted-thatis to say, opened or closed-opened it' it is arranged normally closed, or closed if it is arranged normally open. The signal-Wheel of the transmitting-instrument is furnished with a series of signaling-teeth C, constructed in the usual Way to transmit any signals desired. The signal-wheel G is also furnished with one tooth or cog g', which is longer or Wider than the other-sand extends, preferably, the full Width ot' the sigual-WheeLas is clearly indicated in Fig. 2.
K K are two contact pieces or springs secured to an insulating-support' K2, one ot which K forms part of the main circuit B. The contact finger or spring K forms part of an earth-branch circuit 7c at the signal-box or transmitting-instrume'nt and leading to the earth at k through the movable contact-piece k2 and xed contact 7a2. The movable contact-piece k2 is mounted to move or slide on the signal-box A or on the frame-Work of the l signaling apparatus, and it is adapted to be operated by an arm f', connected with the operating lever or hook F,Which is pulled down to send the special or Warning signal. The movement ot` the operating-lever or crankshaft F rotates the signal-Wheel and at the same time actuates the sliding contact-piece 7a2 to close the earth-branch .circuit 7c, and thus connect the box withv the earth, so that when the si guai-Wheel Gis rotated suiiiciently to bring its long signal-tooth g under the contact-springs K K the signal-box Will be connected With the registering mechanism and annunciai'or-drop magnet at the central station. As the signal-Wheel G revolves, the spring-contactK of course breaks' connection With the long tooth g and thus cuts out the earth branch k almost at the very instant that it is made. The movable contact-piece 7a2 is also returned to place by the backward movement of the starting-lever H, which is returned by the main spring H of the transmitting-instrument,s0 that the earth connection is here broken to prevent the repetition kof the emergency signal and to prevent the earth connection interfering with other signals on the line when the signal-wheel is revolved from the inner lever H. It will be understood that to send the emergency signal through the main circuit B and annunciatorbranch circuit D2 only a momentary closing of the circuit is required, as a single impulse given to the annunciator-drop lever d Will release the drop D, close the alarm-circuit E2, and set the alarm-bell to ringing. The annunciator branch circuit D2 has a ground connection at D2, and when the ground branch k is connected With the main circuit B by the movable contact k2 and by the long tooth g and spring contact-piece K it will be observed that the box is connected in a closed circuit with the annunciator-drop magnet D2, and the moment the annunciator-drop is released this earth circuit is broken at d5 and the alarm-circuit E2 closed by the movement of the drop D. The ground branch c at the transmitting-instrument or signal-box, and also the ground branch D2 at the central ottice, it Will be observed, are by my invention both broken before the signal-wheel G begins to send the signals by the passage of the signaling-teeth g under the contact-spring K'. As the ground connection,whic`n is employed for certaintyin sending the emergency signal, is instantly broken or removed the moment theemergency signal is transmitted, this instantaneous ground connection Will not interfere with the simultaneous operation of other like boXes on the main circuit. The annunciator-drop branch D2 is preferably arranged normally open at cl2 d3, the movement of the registering-lever c closing this branch at cl2 d2 when the main circuit B is iirst opened or broken by the rotation ofthe signaling-Wheel. The closing ot' the annunciator-drop branch may, however, be effected by the closing, instead of the breaking, ot' the main or metallic circuit B, according as such circuit is normally open or closed.
The operation is as follows: Opening the outer door A2 of box A discloses the hook or pull F, which when pulled down engages with the starting-lever Hand sliding ground-plate k2 inside of the inner door A', and thus rotates the circuit-Wheel G,Eig. 2, thereby opening the circuit B at K before the tooth4 g comes in contact with both fingers K K', and thus connecting the earth branch D2 at d2 d3 With the metallic circuit B by releasing the armature-lever c. I It will readily be seen that thus opening the circuit B for an instant and releasing the armature-lever c of the register C in the central office connects the earth IIO 470,666 i y e branch D2 to earth through the contacts 612613 and annunciator-drop D, which earth branch D2 is disconnected by the movement of the drop D the instant the circuit is established through the earth-branch kby the fingers K combination, with a metallic circuit, includ ing a battery and transmitting and receiving instruments, of4 an earth-branch circuit, said transmittinginstrument being provided with mechanism for connecting and immediately disconnecting said branch with said metallic circuit by the operation of said transmittinginstrument prior to its sending the numbersignal, a relay in the metallic circuit operating Whenever said metallic circuit is interrupted to connect said metallic circuit with a Second earth branch at the central office, said second earth branch including an electro-magnetic device which, When energized electrically, operates to open said earthbranch circuit at the central ofice, substantially as speciiied.
2. In a police electrical signaling system, the combination, with a metallic circuit having included therein a battery, a receiving or registering instrument, and a signal-box ,or transmitting-instrumenu of an earthbranch circuit at the signal-box or transmitting-instrument, a movable contact-piece included in said earth branch, means for operating said movable contact-piece to close said earth branch by the movement of the operating lever or hook of the signal-box, and a contact linger or spring operating, in conjunction with the signaling-Wheel of the boX, to connect and immediately disconnect said earth branch with said metallic circuit before the sending of the signal, so that said earthbranch connection may not interfere with the transmission ot' signals over the line by reason of said main line being connected with the ground, substantially as specified.
3. In a police electric signaling system, the Combination, With a metallic circuit, including a battery and transmitting and receiving instruments, of arelayin the metallic circuit, operating' whenever the current in said circuit is interrupted to connect'said metallic circuit to earth through a branch, including an electro-magnetic annunciatordrop device,
which, When energized electrically, operates to open the circuit of the said branch, substantially as and for the purpose described.
4:. In a police electrical signaling system, the combinatiomvvith a metallic circuit having included therein a battery, a receiving or registering instrument, and a signal-box or transmitting-instrument, of an earth-b ran ch circuit at the signal-box or transmitting-instrument, a movable contact-piece included in said earth branch, means for operating said movable contact-piece to close said earth branch by the movement of the operating lever or hook of the signal-box, and a contact finger or spring operating, in conjunction With the signaling-Wheel of the box, to connect and disconnect said earth branch With said metallic circuit, a second earth branch at the central office or receiving-instrument having included therein an annunciatordrop, said second earth branch being closed by a relay operating when the current is interrupted in said metallic circuit and then immediatelybroken or disconnected by the drop, substantially as specified.
5. In a police signaling system, the combination ot metallic circuit B, having magnet B', battery B2, and signaling-Wheel G, furnished With signal-teeth g andv long tooth g l included therein, contact tingers or springs K K', earth-branch circuit k, having contactpiece 7c3 and movable contact-piece k2 included therein, starting-lever H, operating-V lever F, having arm j' engaging said lever H, and arm f engaging'said movable contactplate k2, earth branch Dhavingannunciatordrop D and magnet D included therein, and
' armature-lever c, operating to close said earth branch D2 at d2 d3, substantially as specified. 6. In a police electric signaling system, the combination, with a metallic circuit having included ltherein a battery, a receiving-instrulnent, and a signal-box or transmitting-instruinent, of a ground branch at the signal-box, mechanism for connecting and immediately disconnecting said ground branch with said metallic circuit by the Operation of said transmitting-instrument prior to the transmission of the signal, and a second ground branch at the central oiiice or receivi11g-instrumenthaving included thereinan electro-magnetic annunciator-drop device for opening or disconnecting such ground branch the instant the same is electricallyv energized, the armaturelever of said receiving-instru ment at the first impulse thereof closing said ground branch at the central office, substantially as specified.
LEROY B. FIRMAN.
Witnesses: i
H. M. MUNDAY, EDMUND ADcocK.
roo
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