US1398593A - Alarm system - Google Patents

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US1398593A
US1398593A US369584A US36958420A US1398593A US 1398593 A US1398593 A US 1398593A US 369584 A US369584 A US 369584A US 36958420 A US36958420 A US 36958420A US 1398593 A US1398593 A US 1398593A
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transmitter
switch
switches
contact
magnet
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US369584A
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Richard M Hopkins
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American District Telegraph Co
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American District Telegraph Co
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    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B29/00Checking or monitoring of signalling or alarm systems; Prevention or correction of operating errors, e.g. preventing unauthorised operation

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  • AITORNEX "R. M. HOPKINS.
  • the invention comprises an alarm or signal transmitter adapted to be started in operation for the sounding of asignal, by the operation of any one of a plurality of electric switches; means being provided, however,
  • the invention consists in the combination with means for provisional actuation to the end that a signal may be sent, of means for canceling-the effect of such provisional actuation when desired; and in various other features as hereinafter described, and particularly pointed out in the appended claims.
  • the object of the invention is to provide simple means whereby, in the event of acci- Specification of Letters Patent.
  • F gure 1 is a diagram illustrating one embodlment of the said alarm system, and Fig. 1 is a side view of one of the controlling switches embedded in a floor or other suitable location, a portion of the casing of the switch being sectioned.
  • Fig. 2 shows a front elevation of a transmitter which may be employed in the said system, the said view being a vertical "sec t1on ]11St in rear of the front frame plates of the transmitter.
  • Fig. 3 is a front view of'the transmitter proper;
  • Flg. 4 is a fragmentary front view of the transposing mechanism of the trans.- mltter;
  • Fig. 5 is a fragmentary perspective elevation of the detent mechanism of the transmitter.
  • numeral 1 designates the break wheel of a transmitter, for example, the normally wound electrically controlled transmitter hereinafter described and 2 designates a combination of contact springs or pens, adapted to be actuated by the teeth of the said signal wheel to send an alarm.
  • the particular arrangement of the contact pens or springs so illustrated forms no portion of the present invention, but is claimed in an application of Richard M. Hopkins, Serial-No. 329,730 filed October 10, 1919. It is designed to operate in accordance with the so-called McGulloh system, whereby signals are transmitted both through a metallic and through a ground connection, an whereby, in the event of the breaking of the metallic loop that loop may be divided, by operation of suitable switch!
  • Such 'McCulloh systems are the cam 3, and 5 and 6 designate coactingl contact springs. Normally spring 4 is hel in engagement with one or the other of springs 5 and 6 by cam 3; but/shortly after cam 3 starts to rotate, the spring 4 is caused ,by cam 3 to break contact with that spring,
  • cam 3 and springs 4, 5 and 6 constitute what may be termed a transposing arrangement, the reason for which will be apparent hereafter.
  • 13 designates a suitable battery or other source of electrical energy, and 14 abell, buzzer, or other means for giving a local si al.
  • switch 15-15-15 designate suitable actuating switches by which a circuit from battery 13 through conductor 16, the said switches, contact springs and one or the other of springs 5 and 6,'conductor 17 and magnet 7, back to battery, may be closed by the actuation of one or another of the switches 15.
  • I may state that it is convenient to use a well-known type of four-point switch, actuated by the depression of a button or the like, and which normally, it may be said, closes contact between its points a and b, and c and (i, respectively, but when actuated shifts the connection to close contact between a and c and I; and d, respectively; and vice-versa.
  • the switch is illustrated in a general way in 1, but without any attempt to illustrate its operating mechanism; the said switch being, as stated, a well known article.
  • the circuit is as follows: from battery 13 through conductor 16 to contact point a of the first switch 15,
  • the clock train comprises the usual escapement" 27 mounted on 'the disk 27', which disk carries the usual detent in 28' normally engaging a corresponding etent pin29 on lever 23.
  • This transmitter clock train comprises a cam 30 (which in the actual construction shown is also the spring case of the driving spring of the transmitter clock train) and this cam30 has on its rear side one or more notches 31, one of which normally engages the lever 23.
  • lever 23- when lever 23- is moved aside to permit disengagement of detent pins 28 and 29, lever 23 is moved out of en agement with the notch 31, with which it as previously been in engagement, and cannot return to the detent position until the same or another notch of the cam 30 comes opposite the lever 23.
  • a spring 32 carried by the lever 23 and bearin at ts outer end against the back plate of t e casin forces lever 23 back into engagement with that notch, the detent pin 29 of lever 23 then 1 coming into position to arrest the dome sponding detent pin 28- of the transmitter, I v and thereupon the transmitter is caused to cease operation.
  • the location of the notch or notches of the cam 30 therefore deter- 11 mines the point at which the transmitter ceases operation.
  • this particular transmitter or to any particular means whereb the operation of the switch within a pre etermined period following the first operation of a switch, prevents the sending of a signal.
  • ⁇ Vhat I claim is: a
  • An alarm systm comprising in co bination a transmitter having controlling means including means arranged to provide a predetermined interval of no-signal transmission following actuation of said control ling means in a sense to cause operation of the transmitter, controlling devices operatively connected to said controlling means, and each arranged when operated to operate the transmitter controllin means in a sense to initiate said predetermlned interval of no-signal transmission, and each atranged when operated during that period of no-signal transmission to operate said controlling means of the transmitter to prevent transmission of the signal, and circuit transposing means operated by the transmitter in the event of the transmission of a signal, said transposing means arranged to condition the transmitter for further operation in the event of subsequent operation of one of said controlling devices.
  • An alarm system comprising in combination a magnet-operated controlling means including means arranged to provide a predetermined interval of no-signal transmission following actuation of the controlling magnet in a sense to cause operation of the transmitter, a plurality of controlling switches connected in series with said-magnet and so arranged that operation of one-of said switches changes the magnetic condition of said magnet in a sense to initiate said.
  • circuit tranposing means operated by the transmitter in the event of said transmission-operation of said transmitter, and arranged by its operation to condition the transmitter for further operation in the event of subsequent operation of one of saidcontrolling switches.
  • An alarm system comprising in comscribing witnesses.
  • a transmitter having magnet-operated controlling means and transposm means comprising operating means operate by the transmitter, said transposing means comprising contacts closed and broken alternately during signal-transmitting operation of said transmitter, and controlling switches connected through said alternative contacts to the said transmitter magnet, said switches arranged to provide alternative circuit paths to said alternative contact means of the transposing means, whereby each switch when operated may cause the operation of the transmitter, and whereby after operation of the transmitter subsequent operation of one of said switches causes further operation of the transmitter.
  • each switch when operated may cause the operation of the transmitter, and whereby after operation of the transmitter subsequent operation of one of said switches causes further operation of the transmitter.
  • An alarm system comprising in combination a transmitter having magnet-operated as 'r controlling means and transposing means indluding alternative contacts and an operating cam therefor driven by the transmitter in its signal-transmitting operation, and arranged to break the one and close the other of said alternative contacts by its operation, and a plurality of four-point controlling switches connected to provide alternative circuit paths through the said magnet to said alternative contacts of the transposing means.

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  • Engineering & Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Burglar Alarm Systems (AREA)

Description

R. MPHOPKINS.
ALARM SYSTEM.
APPLICATION FILED MAR. 29, 1920.
L 2. 91. n 9 4 '8 Wm M m3 n m P INVENTOR.
w I ATTORNEY.
R. M. HOPKINS.
ALARM SYSTEM.
APPLICATIOHFILEDMAR. 29, 1920.
1,398,593, Patented Nov-29,1921.
3 SHEETS-SHEET 2.
INVENTOR. I
AITORNEX "R. M. HOPKINS.
ALARM SYSTEM.
APPLICATION FILED,MAR.29,1920.
Patented Nov. 29, '1921.
s SHEETS-SHEET 3.
INVENTUR AITOKNE UNITED STATES PATENT OFFlCE.
mom!) 1:. norxms, or RUTHERFORD, NEW JERSEY, ASSIGNOR 'ro AIERIGAN ms'rmc'r TELEGRAPH comPAN 0F JERSEY c1rY,- NEW JERSEY, A. conr'o- RATION OF NEW JERSEY.
' ing of an alarm by tellers or the like in the event of attempted robbery; but obviously the system is applicable to various uses, and in terming it an alarm system .there is' no intention of limiting its use to the sending of alarms; to the contrary, it may be used for the sending of other signals; for example, it may be used in large manufacturing establishments to sound signals calling for the shutting down of the machinery. The invention comprises an alarm or signal transmitter adapted to be started in operation for the sounding of asignal, by the operation of any one of a plurality of electric switches; means being provided, however,
whereby, if one of such switchesbe actuated, and thereafter within a predetermined interval, the same or any other of the said switches be actuated, then the sending of the saidsignal will be prevented. The reason for this arrangement 'forpreventing the sending of the signal when desired, is that it will frequently happen that a switch will be actuated accidentally or mistakenly; and the person so actuating the switch or some other person having knowledge of the actuation of that switch, and having knowledge that the said actuation was accidental or erroneous, may prevent the sending of an alarm by a further switch actuation.
The invention consists in the combination with means for provisional actuation to the end that a signal may be sent, of means for canceling-the effect of such provisional actuation when desired; and in various other features as hereinafter described, and particularly pointed out in the appended claims. The object of the invention is to provide simple means whereby, in the event of acci- Specification of Letters Patent.
operated controlling mechanism of the ALAEM SYSTEM.
Patented Nov. 29, 1921.
Application filed March 29, 1920. Serial No. 369,584.
I will now proceed to describe the invention with reference to the accompanying drawing in which one arrangement of circuits and apparatus adapted for carrying out theabove object is illustrated, and will then point out the novel features in claims.
In said drawin s:
F gure 1 is a diagram illustrating one embodlment of the said alarm system, and Fig. 1 is a side view of one of the controlling switches embedded in a floor or other suitable location, a portion of the casing of the switch being sectioned.
Fig. 2 shows a front elevation of a transmitter which may be employed in the said system, the said view being a vertical "sec t1on ]11St in rear of the front frame plates of the transmitter. I
. Fig. 3 is a front view of'the transmitter proper; Flg. 4 is a fragmentary front view of the transposing mechanism of the trans.- mltter; Fig. 5 is a fragmentary perspective elevation of the detent mechanism of the transmitter.
Fig. 6 is a side elevation of the magnettransmitter, lookin from the left of Fig. 2. Fig. 7 is a side e evation of the transmitt1n mechanism proper of the transmitter, loo ing from the left of Fig. 2; and Fig. 8 1s a rear view of the controlling cam and spring drum and associated parts, the view being a section on the line 8-8 of Fig. 7.
Referring first to the diagram, Fig. 1: numeral 1 designates the break wheel of a transmitter, for example, the normally wound electrically controlled transmitter hereinafter described and 2 designates a combination of contact springs or pens, adapted to be actuated by the teeth of the said signal wheel to send an alarm.' The particular arrangement of the contact pens or springs so illustrated forms no portion of the present invention, but is claimed in an application of Richard M. Hopkins, Serial-No. 329,730 filed October 10, 1919. It is designed to operate in accordance with the so-called McGulloh system, whereby signals are transmitted both through a metallic and through a ground connection, an whereby, in the event of the breaking of the metallic loop that loop may be divided, by operation of suitable switch! means at the central station, into two separate ground return circuits. Such 'McCulloh systems are the cam 3, and 5 and 6 designate coactingl contact springs. Normally spring 4 is hel in engagement with one or the other of springs 5 and 6 by cam 3; but/shortly after cam 3 starts to rotate, the spring 4 is caused ,by cam 3 to break contact with that spring,
5 or 6, with which it has previously been 1n contact, and to make contact with the other of said springs. The cam 3 and springs 4, 5 and 6 constitute what may be termed a transposing arrangement, the reason for which will be apparent hereafter.
7 designates the controlling magnet, and 8 the oscillating armature of a retard device also forming a portion of the transmitter. Inconnection with the retard device there are springs 9 and 10 normally held separated by an arm 11 projecting from the armature 8; the magnet 7 being normally deenergized and its armature 8 retracted; but inthe event of closing of the circuit through said magnet 7 the armature 8 will be attracted and theasprings 9 and 10 permitted to make-.cgi geact.
13 designates a suitable battery or other source of electrical energy, and 14 abell, buzzer, or other means for giving a local si al.
15-15-15 designate suitable actuating switches by which a circuit from battery 13 through conductor 16, the said switches, contact springs and one or the other of springs 5 and 6,'conductor 17 and magnet 7, back to battery, may be closed by the actuation of one or another of the switches 15. Without limiting myself to any particular type of switch, for use as a switch 15, I may state that it is convenient to use a well-known type of four-point switch, actuated by the depression of a button or the like, and which normally, it may be said, closes contact between its points a and b, and c and (i, respectively, but when actuated shifts the connection to close contact between a and c and I; and d, respectively; and vice-versa. The switch is illustrated in a general way in 1, but without any attempt to illustrate its operating mechanism; the said switch being, as stated, a well known article.
With the switches in the conditions illustrated in the diagram, the circuit is as follows: from battery 13 through conductor 16 to contact point a of the first switch 15,
by the retarding fan train 12 of the trans- 1,aca,aea i then to point b of the said first switch '15, then to point it of the second switch 15, thence to point I) of the second switch 15, thence to point d of the third switch 15, thence to point 0 of the third switch 15 and thence tospring 6; the circuit being broken between springs 6 and 4. If now one of the switches 15v be actuated, for example the second switch 15,, the circuit is shifted from point 6 of the: second switch 15 to point 0 of that second switch 15, thence to point a, of the third switch 15, point b of that third switch 15, contact spring 5, contact spring 4,
conductor 17, magnetfl of the transmitter,
and back to battery. The resultant ener gization of magnet 7 attractsthe armature 8, causing the same to rotate, such movement of the armature being rendered slow mitter (see Fig. 2), with the primary result that arm 1 is caused to move sufliclently to permit co tact springs 9 and 10 to close contact, whereupon circuit is closed from bat-' tery 13 through the local signal dew ice 14, and springs 9 and 10 back to battery, the local signal device 14 being thereby caused to soundits alarm. .As will appear hereafter, however, the break wheel 1 of the transmitter has not yet started in rotation, and therefore as yet no signal is' transmitted by thetransmitter to the central station. But as the armature 8 continues to rotate, after a predetermined interval an arm 18 (Fig. 2) forming a part of the transmitter, trips a detent of that transmitter permitting break wheel 1 and earn 3 tostart in rotation, whereupon the break wheel 1 will actuate the contact pens 2, sending its signal to the central station, and cam 3 will permit sprin 4 to move into contact with spring 6. ut if, after the first actuation of a switch 15, and during the interval preceding the release of the transmitting mechanism of the transmitter, the same switch 15 be actuated again,
or any then the magnet 7 will be denergized through the breaking of its circuit, at the .switch 15 so actuated, the armature 8 and arm 18 will rotate back' to their first'positions, under the influence of a weight 19 (Fig. 2) also forming a part of the transmitter, and the parts are then in effect in their original positions. For example, supposing that during the interval between the first or. provisional actuation of the second switch 15, as above'assumed, and the time when the transmitter detent would otherwise be actuated to start the transmitter mechanism in operation, that second switch 15 be again actuated so that its connections are restored to the condition illustrated in Fig. 1; then the circuit previously closed, through that second switch 15, and contact sprlngs 6 and 4 to conductor 17, etc., will be broken, smce upon its second actuation, secof the other switches be actuated, 110
nd switch 15 closes contact between its points d and b and thence through points at and 0 of the thirdswitch to contact springs 6, the connection between points (1 and 0 of the second switch 15 and thence through the third switch 15, to contact springs 5, being broken. The result of this second actuation of this second switch 15 is obviousl to break the energizing circuit of magnet. and thereby to permitthe armature 8 to move back, as previously stated.
The same result will follow if, after the first actuation of the second switch 15, one
of the other switches 15, for example the first switch 15, be similarly actuated; for in that case contact is shifted between points a and b of first switch 15 to points a and c of said first switch-15, theicircuit thence passing to point a of second switch 15, point I) of that second switch, point it of the third switch 15, point 0 of the third switch 15 and contact spring 6, which latter spring as above stated, is not then in contact with sprin 4. a I
A similar result will follow the actuation of the third switch 15 instead of the first switch 15, following first actuation of any of switches 15'; and if there be still other switches 15, the result of the actuation of any one or" such other. switches following first actuation will be the same viz., to deenergize magnet 7, and prevent the sendingv of a signal by the transmitter.
If, however there be no second switch actuation, within the said predetermined interval, then the transmitter mechanism will be released, break wheel 1 and cam 3 will rotate through one-half rotation of cam 3 and three rotatlons (in the case of the particular transmitter illustrated) of the break wheel; and three rounds of the signal will be transmitted. During this operation the cam 3 will permit spring 4 to shiftto contact with spring 6, the circuit of the magnetous that as armature 8 is caused to move clockwise (in the construction shown) by the attraction of magnet 7, this ratchet pawl will cause the operation of the fan train,'
with consequent retardation of movementof the armature; but when that magnet 7 is deenergized the weight 19 will cause backward rotation of the armature 8, and, with it, backward motion of arm 11 and ratchet pawl- 20, the fan train coming to rest. Arm 18 previously mentioned, also caused to move when the armature 8 is attracted by the magnet, engages at the end of a certain. eriod of its movement, an extension 22 o a pivoted lever 23, which'is the detent lever of the transmitter. This transmitter com prises the usual springdriven clock train 24, one shaft 25 of which carries the cam 3 and another shaft 26 of which carries the break wheel 1. The clock train comprises the usual escapement" 27 mounted on 'the disk 27', which disk carries the usual detent in 28' normally engaging a corresponding etent pin29 on lever 23. When arm 18 encounters and cams to one side the extension 22 of lever 23, the lever disengages detent pin 29 from detent pin 28, thereby permitting, the transmitter clock train to run. This transmitter clock train comprises a cam 30 (which in the actual construction shown is also the spring case of the driving spring of the transmitter clock train) and this cam30 has on its rear side one or more notches 31, one of which normally engages the lever 23. But when lever 23- is moved aside to permit disengagement of detent pins 28 and 29, lever 23 is moved out of en agement with the notch 31, with which it as previously been in engagement, and cannot return to the detent position until the same or another notch of the cam 30 comes opposite the lever 23. When such anotch of the cam does come opposite lever 23: a spring 32, carried by the lever 23 and bearin at ts outer end against the back plate of t e casin forces lever 23 back into engagement with that notch, the detent pin 29 of lever 23 then 1 coming into position to arrest the dome sponding detent pin 28- of the transmitter, I v and thereupon the transmitter is caused to cease operation. The location of the notch or notches of the cam 30 therefore deter- 11 mines the point at which the transmitter ceases operation.
It will be seen that, owing to the action of the transposingcontact device, when the transmitter is operated to send its-signal, 1 and has come to rest, it is in condition to be set in operation anew, by the operation of any one of the switches 15, both for "provisional operation during the no-signal transmission period, and for complete 010- eration, including the transmission of its signal, in the event the switches 15 are operated during such predetermined no-signal transmission. In other words, neither the switches 15, nor the transmitter itself, require resetting after operation, either provisional or complete, except that, of course, after a number of operations of the transmitter its drivin spring must be rewound.
I do not in t is application claim the transmitter provided with retard-control.
' this particular transmitter, or to any particular means whereb the operation of the switch within a pre etermined period following the first operation of a switch, prevents the sending of a signal.
\Vhat I claim is: a
1. An alarm systm comprising in co bination a transmitter having controlling means including means arranged to provide a predetermined interval of no-signal transmission following actuation of said control ling means in a sense to cause operation of the transmitter, controlling devices operatively connected to said controlling means, and each arranged when operated to operate the transmitter controllin means in a sense to initiate said predetermlned interval of no-signal transmission, and each atranged when operated during that period of no-signal transmission to operate said controlling means of the transmitter to prevent transmission of the signal, and circuit transposing means operated by the transmitter in the event of the transmission of a signal, said transposing means arranged to condition the transmitter for further operation in the event of subsequent operation of one of said controlling devices.
2. An alarm system comprising in combination a magnet-operated controlling means including means arranged to provide a predetermined interval of no-signal transmission following actuation of the controlling magnet in a sense to cause operation of the transmitter, a plurality of controlling switches connected in series with said-magnet and so arranged that operation of one-of said switches changes the magnetic condition of said magnet in a sense to initiate said. predetermined interval of no-signal trans mission and that operation of one .of said switches during said interval of no-signal transmission changes the magnetic condition of said magnet in a sense to prevent trans- .v mission of the signal, and circuit tranposing means operated by the transmitter in the event of said transmission-operation of said transmitter, and arranged by its operation to condition the transmitter for further operation in the event of subsequent operation of one of saidcontrolling switches.
3. An alarm system comprising in comscribing witnesses.
bination a transmitter having magnet-operated controlling means and transposm means comprising operating means operate by the transmitter, said transposing means comprising contacts closed and broken alternately during signal-transmitting operation of said transmitter, and controlling switches connected through said alternative contacts to the said transmitter magnet, said switches arranged to provide alternative circuit paths to said alternative contact means of the transposing means, whereby each switch when operated may cause the operation of the transmitter, and whereby after operation of the transmitter subsequent operation of one of said switches causes further operation of the transmitter.
to said alternative contact means of the transposing means, whereby each switch when operated may cause the operation of the transmitter, and whereby after operation of the transmitter subsequent operation of one of said switches causes further operation of the transmitter.
5. An alarm system comprising in combination a transmitter having magnet-operated as 'r controlling means and transposing means indluding alternative contacts and an operating cam therefor driven by the transmitter in its signal-transmitting operation, and arranged to break the one and close the other of said alternative contacts by its operation, and a plurality of four-point controlling switches connected to provide alternative circuit paths through the said magnet to said alternative contacts of the transposing means.
In testimony whereof I have signed this specification 1n the presence of two sub- I RICHARD M. HOPKINS. Witnesses:
CATHERINE J. FLEMING, Douenas P. FOWLER.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3688293A (en) * 1970-05-08 1972-08-29 Standard Farrington Alarm & Si Automatic time-controlled alarm system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3688293A (en) * 1970-05-08 1972-08-29 Standard Farrington Alarm & Si Automatic time-controlled alarm system

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