US2252710A - Radio alarm system - Google Patents

Radio alarm system Download PDF

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US2252710A
US2252710A US212335A US21233538A US2252710A US 2252710 A US2252710 A US 2252710A US 212335 A US212335 A US 212335A US 21233538 A US21233538 A US 21233538A US 2252710 A US2252710 A US 2252710A
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circuit
coil
switch
relay
alarm
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US212335A
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William L Foss
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HOWTON RADIO ALARM Co
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HOWTON RADIO ALARM Co
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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
    • G08B25/008Alarm setting and unsetting, i.e. arming or disarming of the security system

Definitions

  • This invention relates to alarm systems and has as its principal purpose the provision of means insuring the proper setting of the system by an authorized person closing the protected premises, and the elimination of the chance of a false alarm being given as a result of the setting operation.
  • Figure 1 is a diagrammatic representation of the new system in one position, which will be assumed to be night position, and
  • Figure 2 shows the system of Figure 1 in another position here assumed to be day position.
  • the basic alarm system is assumed to be a radio alarm system such as is disclosed, for example, in the copending applications of James O. Howton, Serial No. 184,713, filed January 12., 1938, and Serial No. 191,788, filed February 21, 1938.
  • reference numeral I9 designates a portion of the enclosing wall of the protected premises and reference numeral H a door which is assumed to be the one designated for use by an authorized person closing or opening the premises.
  • a radio transmitter l2 such as is disclosed in the above mentioned applications, the transmitter including an aerial I3 and a ground l4.
  • Operation of the alarm system is initiated by means of a relay whose coil is indicated at I5, and it is here assumed, as in the above applications, that an alarm will be broadcast when the relay coil, for any reason, becomes deenergized.
  • the coil 15 is in immediate control of means such as the movable contact arms l5 corresponding to those shown in Serial No. 191,788.
  • One end of coil is connected by a wire I6 with a source of electric current such as a storage battery I! and this may be the same battery as provided for the alarm message producing apparatus according to the above applications.
  • the battery lead I6 is continued through coil I5 up to a fixed contact I8 of a relay A.
  • a lead I9 from the other side of the battery is in connection with a fixed contact of relay A.
  • the relay includes a pair of contactor arms 2
  • the arms are adapted to be drawn against fixed relay contacts 23 and 24 when the relay coil 25 is energized.
  • Wires 26 and 21 are led from battery I! and constitute what I shall term herein a supply circuit.
  • the wire 26 leads to the switch arm 28 of a switch 29 and the fixed contact of this switch is in connection with the switch arm 39 of a switch 3
  • An alarm or protective circuit 33 is connected between the relay arms Hand 22. It is here assumed to be a burglar circuit and may contain suitable switches suchas the window switches 34 and the door switch 35, which latter is positionedadjacent door H, as here shown.
  • the burglar circuit includes the coil of a magnet 36 with which is cooperative an armature 37 which controls a reciprocable latch 38, the armature being spring-biased away from the magnet.
  • Switches 39 and 49 which may be similar in all respects to switches 29 and 21, include switch arms 41 and 42, respectively.
  • the switch arm H is in connection with wire 26 of the supply circuit through a wire 418 in which is interposed the coil 44 of a relay B.
  • the fixed contact of switch 39 is in connection with wire 21 ofthe supply circuit through a wire 45.
  • Relay 13 includes a pair of fixed contacts which are connected together by a wire 46 and cooperable with these contacts is a pair of contactor arms n and 48 which are movable in unison and normally biased to the open position shown in Figure 1.
  • switch 49 The fixed contact of switch 49 is in connection with wire 28 through a wire 49 in which coil 25 of relay A is interposed.
  • the contact .23 of relay A is also in connection with wire 28 through wire 49, and contact 24 of the relay is in connection with wire 2'! through a wire 59.
  • Arm &2 of switch 40 is in connection with wire 27 through a wire 5
  • a bolt 52 Reciprocably mounted in door II is a bolt 52 which is movable between locking and unlocking positions by means of a key controlled operator 53. On its inner end the bolt carries an insulating pad 54 and on its top surface is provided with a square recess 55. Above the horizontally disposed bolt 52 is a vertically reciprocable detent 56. A pin 57 fixed in the upper end of the detent is engaged in a cam slot 58 formed in a disc 59 of insulating material. Disc 59 is mounted on andforms a part of a rotary key-controlled operator 99.
  • Disc 59 has three radiallyprojecting fingers 6
  • the disc is also provided with a square peripheral notch 54 which in the day time position of the disc, Figure 2, is engageable by latch 38.
  • the alarm circuit cannot affect the condition of coil l5 which remains energizedby reason of the short circuit, but since the alarm circuit is in connection with the supply circuit it may be tested as required.
  • disc 59 When the. premises are to be entered, disc 59 must first be. rotated to the position of Figure2, since until this is done and the detent thereby elevated, bolt 52 cannot be moved. With the disc returned to the-position of Figure 2, switches 3
  • disturbance of a burglar circuit is meant the affecting of the circuit, in a manner appropriate to the particular circuit to disturb its normal current condition so that it is conditioned to cause operation of the alarm signal means.
  • a source of electric current a circuit in connection with said source, a protective circuit, alarm signal producing means, a coil, means controlled by said coil for initiating operation of said signal producing means, another circuit in parallel with said first circuit and connected to said source and in which said coil is connected in series, and switch means operable to connect said alarm circuit with said supply circuit or with said leads.
  • a source of electric current a circuit in connection with said source, a protective circuit, alarm signal producing means, a coil, means controlled by said coil for initiating operation of said signal producing means, another circuit in parallel with said first circuit and connected to said source and in which said coil is connected in series, switch means operable to connect said alarm circuit With either of said circuits connected to said source, and means effective when the protective circuit is in disturbed condition for preventing operation of said switch means to transfer the protective circuit from said first-named circuit to said parallel circuit.
  • a source of electric current a circuit in connection with said source, a protective circuit, alarm signal producing means, a coil, means controlled by said coil for initiating operation of said signal producing means, another circuit in parallel with said first circuit and connected to said source and in which said coil is connected in series, switch means operable to connect said alarm circuit with either of said circuits connected to said source and means effective when the protective circuit is in disturbed condition for preventing operation of said switch means to transfer the protective circuit from said first-named circuit to said parallel circuit, said last-named means including electromagnetic means controlled in dependence upon the condition of said protective circuit.
  • a source-of electric current a circuit in connection with said source, a protective circuit, alarm signal producing means, a coil, means controlled by said coil for initiating operation of said signal producing means, another circuit in parallel with said first circuit and connected'to said source and in which said coil is connected in series, a shorting circuit for said parallel circuit,
  • a source of electric current a circuit in connection with said source, alarm signal producing means, a coil, means controlled by said coil for initiating operation of said signal producing means, another circuit in parallel with said first circuitand connected to said source and in which said coil is connected in series, a shorting circuit for said parallel circuit, a switch in said shorting circuit, switch means operable to connect said protective circuit with either of said circuits connected to said source, and a common control member for said switch and switch means manipulatable to cause the latter to transfer the protective circuit from the first-named circuit to said parallel circuit and then to cause opening of said switch, said control member being reversely manipulatable to cause closing of said switch and then to cause said switch means to transfer the protective circuit from said parallel circuit to said first-named circuit.
  • a coil means controlled by said coil for initiating operaton of said signal producing means, another circuit in parallel with said first circuit and connected to said source and in which said coil is connected in a series, a shorting circuit for said parallel circuit, a relay controlling said shorting circuit, a circuit for said relay in connection with said first-named circuit, a switch in said relay circuit, a second relay arranged to transfer said protective circuit between either of said circits connected to said source, a circuit for said second relay in connection with said firstnamed circuit, a switch in the last named circuit, and a common operator for said switches so arranged that upon its manipulation the protective circuit is transferred from the first-named circuit to said parallel circuit and the shorting circuit is broken and that upon reverse manipulation the shorting circuit is made and the protective circuit is then transferred from said parallel circuit to the first-named circuit.
  • a source of electric current a circuit in connection with said source, a protective circuit, alarm signal producing means, a coil, means controlled by said coil for initiating operation of said signal producing means, another circuit in parallel with said first circuit and connected to said source and in which said coil is connected in series, a shorting circuit for said parallel circuit, a relay controlling said shorting circuit, a circuit for said relay, a switch in said relay circuit, a second relay arranged to transfer said protective circuit between said firstnamed circuit and said parallel circuit, a circuit for said second relay in connection with said first-named circuit, a switch in the last-named circuit, a common operator for said switches so arranged that upon its manipulation the protective circuit is transferred from the first-named circuit to said parallel circuit and the shorting circuit is broken and that upon reverse manipulation the shorting circuit is made and the protective circuit is then transferred from said parallel circuit to the first-named circuit, and means effective when the protective circuit is in disturbed condition for preventing operation of said operator to transfer the alarm circuit from the first-named circuit
  • a source of electric current a circuit in connection with said source, a protective circuit, alarm signal producing means, a coil, means controlled by said coil for initiating operation of said signal producing means, another circuit in parallel with said first circuit and connected to said source and in which said coil is connected in series, a shorting circuit for said parallel circuit, a relay controlling said shorting circuit, a circuit for said relay, a switch in said relay circuit, a second relay arranged to transfer said protective circuit between said firstnamed circuit and said parallel circuit, a circuit for said second relay in connection With said first-named circuit, a switch in the last-named circuit, a common operator for said switches so arranged that upon its manipulation the protective circuit is transferred from the first-named circuit to said parallel circuit and the shorting circuit is broken and that upon reverse manipulation the shorting circuit is made and the protective circuit is then transferred from said parallel circuit to the first-named circuit, means effective when the protective circuit is in disturbed condition for preventing operation of said operator to transfer the protective circuit from the first-named circuit to

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  • Engineering & Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Burglar Alarm Systems (AREA)

Description

Aug. 19, 1941. w. L. FOSS RADIC'*ALARM SYSTEM Filed June 7, 1938 Patented Aug. 19, 1941 RADIO ALARM SYSTERI William L. Foss, Washington, D. 0., assignor to Howton Radio Alarm Company, Seattle, Wash.
Application June 7, 1938, Serial No. 212,335
8 Claims.
This invention relates to alarm systems and has as its principal purpose the provision of means insuring the proper setting of the system by an authorized person closing the protected premises, and the elimination of the chance of a false alarm being given as a result of the setting operation. By way of illustration of the invention, I have shown a practical embodiment thereof in the accompanying drawing with reference to which the description will proceed.
In the drawing:
Figure 1 is a diagrammatic representation of the new system in one position, which will be assumed to be night position, and
Figure 2 shows the system of Figure 1 in another position here assumed to be day position.
For the purpose of illustration, the basic alarm system is assumed to be a radio alarm system such as is disclosed, for example, in the copending applications of James O. Howton, Serial No. 184,713, filed January 12., 1938, and Serial No. 191,788, filed February 21, 1938.
Referring to the drawing, reference numeral I9 designates a portion of the enclosing wall of the protected premises and reference numeral H a door which is assumed to be the one designated for use by an authorized person closing or opening the premises. Within the premises is disposed a radio transmitter l2 such as is disclosed in the above mentioned applications, the transmitter including an aerial I3 and a ground l4. Operation of the alarm system is initiated by means of a relay whose coil is indicated at I5, and it is here assumed, as in the above applications, that an alarm will be broadcast when the relay coil, for any reason, becomes deenergized. The coil 15 is in immediate control of means such as the movable contact arms l5 corresponding to those shown in Serial No. 191,788.
One end of coil is connected by a wire I6 with a source of electric current such as a storage battery I! and this may be the same battery as provided for the alarm message producing apparatus according to the above applications. The battery lead I6 is continued through coil I5 up to a fixed contact I8 of a relay A. A lead I9 from the other side of the battery is in connection with a fixed contact of relay A. The relay includes a pair of contactor arms 2| and 22 movable in unison and normally springbiased against contacts 18 and 20, respectively.
The arms are adapted to be drawn against fixed relay contacts 23 and 24 when the relay coil 25 is energized.
Wires 26 and 21 are led from battery I! and constitute what I shall term herein a supply circuit. The wire 26 leads to the switch arm 28 of a switch 29 and the fixed contact of this switch is in connection with the switch arm 39 of a switch 3|. Both of these arms are spring-biased toward closed position.
The fixed contact of switch 3| is lead to one terminal of a buzzer, or other suitable signaling device 32; Wire 21 leads to the other terminal of the buzzer. 7
An alarm or protective circuit 33 is connected between the relay arms Hand 22. It is here assumed to be a burglar circuit and may contain suitable switches suchas the window switches 34 and the door switch 35, which latter is positionedadjacent door H, as here shown. The burglar circuit includes the coil of a magnet 36 with which is cooperative an armature 37 which controls a reciprocable latch 38, the armature being spring-biased away from the magnet.
Switches 39 and 49, which may be similar in all respects to switches 29 and 21, include switch arms 41 and 42, respectively. The switch arm H is in connection with wire 26 of the supply circuit through a wire 418 in which is interposed the coil 44 of a relay B. The fixed contact of switch 39 is in connection with wire 21 ofthe supply circuit through a wire 45. Relay 13 includes a pair of fixed contacts which are connected together by a wire 46 and cooperable with these contacts is a pair of contactor arms n and 48 which are movable in unison and normally biased to the open position shown in Figure 1.
The fixed contact of switch 49 is in connection with wire 28 through a wire 49 in which coil 25 of relay A is interposed. The contact .23 of relay A is also in connection with wire 28 through wire 49, and contact 24 of the relay is in connection with wire 2'! through a wire 59. Arm &2 of switch 40 is in connection with wire 27 through a wire 5|.
Reciprocably mounted in door II is a bolt 52 which is movable between locking and unlocking positions by means of a key controlled operator 53. On its inner end the bolt carries an insulating pad 54 and on its top surface is provided with a square recess 55. Above the horizontally disposed bolt 52 is a vertically reciprocable detent 56. A pin 57 fixed in the upper end of the detent is engaged in a cam slot 58 formed in a disc 59 of insulating material. Disc 59 is mounted on andforms a part of a rotary key-controlled operator 99.
Disc 59 has three radiallyprojecting fingers 6|, 62 and 63 cooperable with the switch arms 30,
4! and 42 respectively. The disc is also provided with a square peripheral notch 54 which in the day time position of the disc, Figure 2, is engageable by latch 38.
In the day time position of the parts, as shown through arms 2| and 22 and contacts 23 and 24.
of relay A. The alarm circuit cannot affect the condition of coil l5 which remains energizedby reason of the short circuit, but since the alarm circuit is in connection with the supply circuit it may be tested as required.
The person authorized to close the. premises'j for the night leaves by the door H and upon.
closing the door switch is closed. Disc 59 cannot be turned since detent 56. is. out of: re ister with notch of bolt152 and consequently the first operation must be to move the bolt to the locked position of Figure I wherein it engages in a recess in the jamb;35, recess, 55 being thus brought under detent 53; If; the alarm circuit is intact latch 33 will be in the position shown in both figures, but if there is a break in the circuit, magnet 36 will be. deenergized and the latch 38 will be engaged in notch 65 of disc 59. The personiclosing the premises has been reminded by thev buzzer ,32 that disc 59 must be set, since when. bolt '52 was movedto locking position, switch; 29. closed and established, the buzzer circuit. If the disccannot be turned the premises must, be reenteredandinvestigatcd for open windows and the. like.
If the. alarm circuit is intact disc 53, through operator 6!], is readily movable in a counterclockwise direction so that detent 56 is projected into notchv 55 and the switches 31, 39 and 43 are opened, as shown in Figure 1.
Due to the opening of switch 31. the buzzer circuit is broken. Switch 43 is opened prior. to
switch 39 so that coil 44 of relay B is deenergized subsequent to the deenergization. of coil 25 of relay A. With coil 25 deenergized arms 21 and, 22 move against contacts 18; and 23, respectively, so that the alarm circuit 33 is switched to the leads l3 and I9. Upon the deenergization of coil 44 the relay arms 4'! and 48 move to the position shown in Figure 1. wherein the short circuit is brokenand consequently the alarm circuit. 33, through the leads l6 and i9, is in control. of coil l5 which remains energized unless circuit 33- is broken. at some point. Upon such occurrence the deenergization of coil l5 will cause an. appropriate alarm signal to be given.
When the. premises are to be entered, disc 59 must first be. rotated to the position of Figure2, since until this is done and the detent thereby elevated, bolt 52 cannot be moved. With the disc returned to the-position of Figure 2, switches 3|, 39 and 40 resume their closed position and buzzer 32 will; operate until. bolt 52 is retracted. Switch 39 closes before switch 43 so that the shorting circuit is established prior to the transfer of the alarm circuit to the supply. circuit through contacts 23 and24 of relay A, Figure 2.
The disclosure herein is to be taken. as illustrative only, since the invention is susceptible of varied embodiment. without departure from the claims which follow; I do not claim per se the disclosed bolt, detent, anddetent operator, these: features being covered in the copending ,a protective circuit,
application of James O. Howton, Serial No. 212,380 filed June 7, 1938.
In referring, in the claims, to disturbance of a burglar circuit, is meant the affecting of the circuit, in a manner appropriate to the particular circuit to disturb its normal current condition so that it is conditioned to cause operation of the alarm signal means.
I claim:
1. In an alarm system, a source of electric current, a circuit in connection with said source, a protective circuit, alarm signal producing means, a coil, means controlled by said coil for initiating operation of said signal producing means, another circuit in parallel with said first circuit and connected to said source and in which said coil is connected in series, and switch means operable to connect said alarm circuit with said supply circuit or with said leads.
2. In an alarm system, a source of electric current, a circuit in connection with said source, a protective circuit, alarm signal producing means, a coil, means controlled by said coil for initiating operation of said signal producing means, another circuit in parallel with said first circuit and connected to said source and in which said coil is connected in series, switch means operable to connect said alarm circuit With either of said circuits connected to said source, and means effective when the protective circuit is in disturbed condition for preventing operation of said switch means to transfer the protective circuit from said first-named circuit to said parallel circuit.
3. In an alarm system, a source of electric current, a circuit in connection with said source, a protective circuit, alarm signal producing means, a coil, means controlled by said coil for initiating operation of said signal producing means, another circuit in parallel with said first circuit and connected to said source and in which said coil is connected in series, switch means operable to connect said alarm circuit with either of said circuits connected to said source and means effective when the protective circuit is in disturbed condition for preventing operation of said switch means to transfer the protective circuit from said first-named circuit to said parallel circuit, said last-named means including electromagnetic means controlled in dependence upon the condition of said protective circuit.
4. In an alarm. system for enclosed premises, a source-of electric current, a circuit in connection with said source, a protective circuit, alarm signal producing means, a coil, means controlled by said coil for initiating operation of said signal producing means, another circuit in parallel with said first circuit and connected'to said source and in which said coil is connected in series, a shorting circuit for said parallel circuit,
-a switch in said shorting circuit operable from the exterior of the premises by an authorized person, and swimh means operable to connect said alarm circuit with either of said circuits connectedto said source.
5. In an alarm system, a source of electric current, a circuit in connection with said source, alarm signal producing means, a coil, means controlled by said coil for initiating operation of said signal producing means, another circuit in parallel with said first circuitand connected to said source and in which said coil is connected in series, a shorting circuit for said parallel circuit, a switch in said shorting circuit, switch means operable to connect said protective circuit with either of said circuits connected to said source, and a common control member for said switch and switch means manipulatable to cause the latter to transfer the protective circuit from the first-named circuit to said parallel circuit and then to cause opening of said switch, said control member being reversely manipulatable to cause closing of said switch and then to cause said switch means to transfer the protective circuit from said parallel circuit to said first-named circuit.
6. In an alarm system, a source of electric current, a circuit in connection with said source, a protective circuit, alarm signal producing means,
a coil, means controlled by said coil for initiating operaton of said signal producing means, another circuit in parallel with said first circuit and connected to said source and in which said coil is connected in a series, a shorting circuit for said parallel circuit, a relay controlling said shorting circuit, a circuit for said relay in connection with said first-named circuit, a switch in said relay circuit, a second relay arranged to transfer said protective circuit between either of said circits connected to said source, a circuit for said second relay in connection with said firstnamed circuit, a switch in the last named circuit, and a common operator for said switches so arranged that upon its manipulation the protective circuit is transferred from the first-named circuit to said parallel circuit and the shorting circuit is broken and that upon reverse manipulation the shorting circuit is made and the protective circuit is then transferred from said parallel circuit to the first-named circuit.
7. In an alarm system, a source of electric current, a circuit in connection with said source, a protective circuit, alarm signal producing means, a coil, means controlled by said coil for initiating operation of said signal producing means, another circuit in parallel with said first circuit and connected to said source and in which said coil is connected in series, a shorting circuit for said parallel circuit, a relay controlling said shorting circuit, a circuit for said relay, a switch in said relay circuit, a second relay arranged to transfer said protective circuit between said firstnamed circuit and said parallel circuit, a circuit for said second relay in connection with said first-named circuit, a switch in the last-named circuit, a common operator for said switches so arranged that upon its manipulation the protective circuit is transferred from the first-named circuit to said parallel circuit and the shorting circuit is broken and that upon reverse manipulation the shorting circuit is made and the protective circuit is then transferred from said parallel circuit to the first-named circuit, and means effective when the protective circuit is in disturbed condition for preventing operation of said operator to transfer the alarm circuit from the first-named circuit to said parallel circuit.
8. In an alarm system, a source of electric current, a circuit in connection with said source, a protective circuit, alarm signal producing means, a coil, means controlled by said coil for initiating operation of said signal producing means, another circuit in parallel with said first circuit and connected to said source and in which said coil is connected in series, a shorting circuit for said parallel circuit, a relay controlling said shorting circuit, a circuit for said relay, a switch in said relay circuit, a second relay arranged to transfer said protective circuit between said firstnamed circuit and said parallel circuit, a circuit for said second relay in connection With said first-named circuit, a switch in the last-named circuit, a common operator for said switches so arranged that upon its manipulation the protective circuit is transferred from the first-named circuit to said parallel circuit and the shorting circuit is broken and that upon reverse manipulation the shorting circuit is made and the protective circuit is then transferred from said parallel circuit to the first-named circuit, means effective when the protective circuit is in disturbed condition for preventing operation of said operator to transfer the protective circuit from the first-named circuit to said parallel circuit, said last-named means including electromagnetic means controlled in dependence upon the condition of said protective circuit.
WILLIAM L. FOSS.
US212335A 1938-06-07 1938-06-07 Radio alarm system Expired - Lifetime US2252710A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2474757A (en) * 1945-06-04 1949-06-28 Sebastiano D Amico Burglary or fire alarm system
US2574696A (en) * 1949-03-03 1951-11-13 John Nathanson Radio alarm transmitting, recording, and signaling system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2474757A (en) * 1945-06-04 1949-06-28 Sebastiano D Amico Burglary or fire alarm system
US2574696A (en) * 1949-03-03 1951-11-13 John Nathanson Radio alarm transmitting, recording, and signaling system

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