U.S. patent number 3,631,433 [Application Number 04/857,882] was granted by the patent office on 1971-12-28 for detection and alarm system.
This patent grant is currently assigned to Fire Protection Company. Invention is credited to Keith M. Dix.
United States Patent |
3,631,433 |
Dix |
December 28, 1971 |
DETECTION AND ALARM SYSTEM
Abstract
A fire detection and alarm system for sensing a dangerous fire
or like condition in one part of a building or the like and
providing an alarm signal at a remote location in the building, by
means of high-frequency carrier signals superimposed on the
existing wiring, including a fire detection transmitter for sensing
fire and transmitting at one frequency, a receiver responsive to
signals from the fire transmitter for actuating an alarm, a
normally energized supervisory transmitter adjacent the
fire-detecting transmitter and operative at a second frequency for
sensing circuit failure, and a supervisory receiver at the remote
location responsive to signals from the supervisory transmitter for
actuating an alarm on power failure when the supervisory
transmitter stops sending. In an alternative embodiment for use in
a large building involving many different widespread areas, a
separate fire detection transmitter is provided in each area in
association with a stepping relay which identifies the area, and an
annunciator at the remote alarm location includes a single stepping
relay for selectively energizing indicators not only warning of
fire or the like but also showing the location.
Inventors: |
Dix; Keith M. (Bannockburn,
IL) |
Assignee: |
Fire Protection Company
(N/A)
|
Family
ID: |
25326939 |
Appl.
No.: |
04/857,882 |
Filed: |
September 15, 1969 |
Current U.S.
Class: |
340/509; 340/8.1;
340/518; 340/541; 340/538; 340/593 |
Current CPC
Class: |
G08B
25/06 (20130101) |
Current International
Class: |
G08B
25/06 (20060101); G08B 25/01 (20060101); G08b
001/08 () |
Field of
Search: |
;340/164,164A,168A,215,216,416 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Caldwell; John W.
Assistant Examiner: Trafton; David L.
Claims
I claim:
1. A detection and alarm system utilizing high frequency signals
transmitted over existing wiring in a building or the like,
comprising,
a. a fire-detecting transmitter circuit located for sensing a
dangerous fire condition and transmitting signals,
b. a fire alarm receiver circuit located remotely from the
fire-detecting transmitter circuit for receiving signals
transmitted by the fire detecting transmitter circuit and
indicating a fire condition,
c. a supervisory transmitter circuit associated with the
fire-detecting transmitter circuit and normally energized to
transmit signals when the fire-detecting circuit is in operative
condition, and
d. a warning receiver circuit located adjacent the fire alarm
receiver circuit for normally receiving signals from the
supervisory transmitter circuit and indicating a warning on failure
to receive.
2. A detection and alarm system as defined in claim 1, wherein the
fire-detecting transmitter includes fire detection means for
sensing a dangerous fire condition, and a transmitter energizable
responsive to the detection means in event of said condition for
transmitting signals.
3. A detection and alarm system as defined in claim 1, wherein the
fire alarm receiver circuit includes a receiver for receiving
signals when transmitted by the fire-detecting transmitter, and an
indicator energizable responsive to the alarm receiver when
receiving.
4. A detection and alarm system as defined in claim 1, wherein the
supervisory transmitter circuit includes a transmitter for sending
signals when energized, and a power supply common to the
fire-detecting transmitter circuit and the supervisory transmitter
circuit for normally maintaining the supervisory transmitter
energized in the absence of power failure.
5. A detection and alarm system as defined in claim 1, wherein the
warning receiver circuit includes a receiver for receiving signals
when transmitted by the supervisory transmitter, and an indicator
energizable responsive to the warning receiver on failure to
receive.
6. A fire detection and alarm system for utilizing high frequency
signals transmitted over existing wiring in a building or the like,
comprising,
a. a fire-detecting transmitter adapted to be connected to the
existing wiring for power supply including means for sensing a
dangerous fire condition and means responsive to the sensing means
for transmitting signals of a first predetermined frequency over
the existing wiring indicative of the fire condition,
b. a fire alarm receiver adapted to be connected to the existing
wiring for power supply and located remotely from the
fire-detecting transmitter including means for receiving signals of
said first frequency from the existing wiring transmitted by the
fire-detecting transmitter and means responsive to the receiving
means for issuing an alarm indicating a fire condition,
c. a supervisory transmitter associated with the fire-detecting
transmitter and adapted to be connected with the existing wiring
for power supply including means normally energized thereby to
transmit signals of a second predetermined frequency over the
existing wiring when the power supply to the fire-detecting
transmitter is operative, and
d. a warning receiver associated with the fire alarm receiver and
adapted to be connected to the existing wiring for power supply
including means for normally receiving signals of said second
frequency from the existing wiring transmitted by the supervisory
transmitter and means responsive to the receiving means for issuing
a warning indicating trouble on failure to receive.
7. A combination as defined in claim 6,
said sensing means including a normally open sensing switch in
circuit with a normally deenergized high current relay controlling
said transmitting means of the first frequency,
said supervisory transmitter including a normally energized
low-current relay controlling said transmitting means of the second
frequency and in circuit with a source of power and the
high-current relay,
and a relatively high resistance in parallel with the normally open
sensing switch,
so that the supervisory low-current relay is normally energized in
the absence of failure of the power source and is deenergized on
failure of the power source, and the detecting low-current relay is
normally deenergized and becomes energized on closure of the
sensing switch.
8. A detection and alarm system as defined in claim 6,
said fire-detecting transmitter including an oscillator in circuit
with a normally open switch,
a normally deenergized high-current relay coil controlling said
normally open switch, and
a normally open fire-detecting switch in circuit with the normally
deenergized relay coil and adapted to be closed in response to a
dangerous fire condition to energize the relay coil, thereby to
close the relay switch and energize the oscillator to transmit
signals to the fire alarm receiver.
9. A combination as defined in claim 8,
said supervisory transmitter comprising an oscillator in circuit
with relay switch contacts, and
a normally energized low-current relay coil holding the switch
contacts closed in the absence of power failure.
10. A combination as defined in claim 9,
said fire detection transmitter and said supervisory transmitter
including a common control circuit having said relay coils in
series circuit and in series with at least one normally open fire
detection switch, and
a relatively high resistance in parallel with the fire detection
switch and completing a circuit to maintain the supervisory relay
normally energized in the absence of power failure, the arrangement
being such that on closure of the fire detection switch the
resistance is shunted and the detecting relay is energized.
11. A combination as defined in claim 6, wherein the warning means
in the warning receiver includes a battery normally connected with
the existing wiring for charging, an indicator and a normally
nonconductive switching device in circuit with the battery and
means controlled by the warning receiver for rendering the
switching device conductive on failure to receive, said alarm means
in the alarm receiver comprising an indicator and a normally
nonconductive switching device in circuit with the existing wiring,
and means controlled by the fire alarm receiver for rendering the
switching device conductive on receiving.
12. A combination as defined in claim 6, including a local alarm
associated with the fire alarm detecting transmitter including an
indicator and a normally nonconductive switching device in circuit
with the existing wiring together with means controlled by the
transmitter for rendering the switching device conductive during
transmission, and a local alarm associated with the supervisory
transmitter including a battery in circuit with the existing wiring
to normally be charged thereby, an indicator and a normally
nonconductive switching device in circuit with the battery together
with means responsive to the supervisory transmitter for rendering
the switching device conductive on failure to transmit.
13. In an alarm system for protecting a plurality of different
areas in a building or the like and indicating trouble at a single
remote location and identifying the area of trouble,
a. a rotary switch associated with each area including means for
advancing a movable contact one or more increments to a stationary
contact located at a different increment for each area,
b. a trouble-indicating switch in each area in circuit with the
advancing means and with a source of power and operable for
energizing the advancing means in event of trouble,
c. an interruptor associated with each advancing means operable to
stop the movable contact at the stationary contact located at a
different increment for each area,
d. a transmitter associated with each rotary switch and energized
once for each increment of movement of the associated movable
contact for transmitting a signal,
e. a receiver energizable responsive to signals from any of the
transmitters,
f. an annunciator at an indicating station having means responsive
to receiver energization for advancing a movable contact relative
to a plurality of stationary contacts a distance of one stationary
contact for each receiver energization, and
g. a plurality of indicating devices in circuit respectively with
the stationary annunciator contacts each for indicating trouble in
a different area and identifying the area.
14. In an alarm system for protecting a plurality of different
areas in a building or the like and indicating trouble at a single
remote location and identifying the area of trouble,
a. a plurality of stepping switches one associated with each area,
each including means for advancing a movable contact relative to a
plurality of stationary contacts,
b. a trouble-indicating switch in each area in circuit with the
advancing means and with a source of power and operable for
energizing the advancing means in event of trouble,
c. an interrupt switch in circuit with each advancing means and
operable to deenergize the same,
d. an interruptor for each area operable at a different position of
the movable contact for each area to actuate the interrupt
switch,
e. a signal switch associated with each stepping switch actuated
repeatedly once for each stationary contact traversed by the
movable contact,
f. a transmitter in circuit with each signal switch to be
momentarily energized on each switch actuation for transmitting a
signal,
g. a receiver energizable responsive to signals from any of the
transmitters,
h. an annunciator at an indicating station having means responsive
to receiver energization for advancing a movable contact relative
to a plurality of stationary contacts a distance of one stationary
contact for each receiver energized, and
i. a plurality of indicating devices in circuit respectively with
the stationary annunciator contacts each for indicating trouble in
a different area and identifying the area.
15. In an alarm system for protecting a plurality of different
areas in a building or the like and indicating trouble at a single
remote location and identifying the area of trouble,
a. a plurality of stepping relays one associated with each area,
each including a coil for stepping a movable contact relative to a
plurality of stationary contacts,
b. a trouble-indicating switch in each area in contact with the
stepping coil and with a source of power and operable for
energizing the stepping coil in event of trouble,
c. an interrupt switch in circuit with each stepping coil operable
to deenergize the same,
d. an interrupt coil for each area in circuit with a different
stationary contact for each area energizable to actuate the
interrupt switch at a different position in each area,
e. a signal switch with each stepping relay actuated once for each
stationary contact traversed by the movable contact,
f. a transmitter in circuit with each signal switch and energized
momentarily on each switch actuation for transmitting a signal,
g. a receiver energizable momentarily responsive to each signal
from any of the transmitters,
h. a control switch operated momentarily responsive to each
receiver energization,
i. an annunciator relay at an indicating station having a stepping
coil controlled by said receiver switch for advancing a movable
contact relative to a plurality of stationary contacts a distance
of one stationary contact for each control switch actuation,
and
j. a plurality of indicating lamps in circuit respectively with the
last-recited stationary contacts each for indicating trouble in a
different area and identifying the trouble area.
16. A combination as defined in claim 15, each stepping relay
including a pawl and ratchet device having a pawl attractable by
said stepping coil and a ratchet actuated by the pawl for advancing
the movable switch contact responsive to operation of the
trouble-indicating switch, a stepper switch in circuit with the
stepper coil and operated by the pawl on each actuation of the
latter thereby to deenergize the coil, and
means for returning the pawl to close the stepper switch thereby to
reenergize the stepper coil for the next step.
17. A combination as defined in claim 15 wherein said annunciator
relay includes a pawl and ratchet device having a pawl attractable
by said stepper coil and a ratchet actuated by the pawl for driving
the movable contact, and means for returning the pawl on
deenergization of the stepper coil.
18. In an alarm system for protecting a plurality of different
areas in a building or the like and indicating trouble at a single
remote location and identifying the area of trouble, utilizing high
frequency carrier signals transmitted over existing wiring,
a. a rotary switch associated with each area including means for
advancing a movable contact one or more increments to a stationary
contact located at a different increment for each area,
b. a trouble-indicating switch in each area in circuit with the
advancing means and with a source of power and operable for
energizing the advancing means in event of trouble,
c. an interruptor associated with each advancing means operable to
stop the movable contact at the stationary contact located at a
different increment for each area,
d. an alarm transmitter associated with each rotary switch and
energized once for each increment of movement of the associated
movable contact for transmitting a signal,
e. an alarm receiver energizable responsive to signals from any one
of the alarm transmitters,
f. an annunciator at an indicating station having means responsive
to alarm receiver energization for advancing a movable contact
relative to a plurality of stationary contacts a distance of one
stationary contact for each alarm receiver energization,
g. a plurality of indicating devices in circuit respectively with
the stationary annunciator contacts each for indicating trouble in
a different area and identifying the area,
h. means connecting each alarm transmitter to the existing building
wiring for power supply,
i. means connecting the alarm receiver to the existing wiring for
power supply,
j. a supervisory transmitter connected to the existing wiring for
power supply adjacent the most remote alarm transmitter and
normally energized to transmit signals when the power supply is
operative, and
k. a supervisory receiver connected to the existing wiring for
power supply adjacent the alarm receiver for normally receiving
signals from the supervisory transmitter and indicating a warning
on failure of power supply to the supervisory transmitter or
supervisory receiver.
19. A combination as defined in claim 18 including
a normally open sensing switch in each area in circuit with a
normally deenergized high current relay controlling the associated
trouble-indicating switch.
20. A combination as defined in claim 19 including a normally
energized low-current relay controlling the supervisory transmitter
and in circuit with the high current relay in the most remote area
and the existing wiring for power supply, a relatively high
resistance in parallel with the normally open sensing switch in the
most remote area so that the supervisory low current relay is
normally energized in the absence of failure of the power source
and is deenergized on failure of the power source, and the
detecting low-current relay is normally deenergized and becomes
energized on closure of the sensing switch.
21. In an alarm system for protecting a plurality of different
areas in a building or the like and indicating trouble at a single
remote location and identifying the area of trouble,
a. a transmitter associated with each area for sending signals
therefrom,
b. means for energizing each transmitter momentarily a different
number of times to indicate trouble and the source thereof by the
number of signals sent,
c. a receiver energizable responsive to signals from any of the
transmitters,
d. an annunciator at an indicating station having means responsive
to receiver energization for advancing a movable contact relative
to a plurality of stationary contacts a distance of one stationary
contact for each receiver energization, and
e. a plurality of indicating devices in circuit respectively with
the stationary annunciator contacts each for indicating trouble in
a different area and identifying the area.
22. In an alarm system for protecting a plurality of different
areas in a building or the like and indicating trouble at a single
remote location and identifying the area of trouble,
a. a rotary switch associated with each area including means for
advancing a movable contact one or more increments to a stationary
contact located at a different increment for each area,
b. a trouble-indicating switch in each area in circuit with the
advancing means and with a source of power and operable for
energizing the advancing means in event of trouble,
c. an interruptor associated with each advancing means operable to
stop the movable contact at the stationary contact located at a
different increment for each area,
d. a transmitter associated with each rotary switch and energized
once for each increment of movement of the associated movable
contact for transmitting a signal,
e. a receiver energizable responsive to signals from any of the
transmitters,
f. a plurality of indicating devices each for indicating trouble in
a different area and identifying the area, and
g. means responsive to the receiver for selectively energizing the
indicating devices depending on the number of signals received.
23. In an alarm system for protecting a plurality of different
areas in a building or the like and indicating trouble at a single
remote location and identifying the area of trouble,
a. a transmitter associated with each area for sending signals
therefrom,
b. means for energizing each transmitter momentarily a different
number of times to indicate trouble and the source thereof by the
number of signals sent,
c. a receiver energizable responsive to signals from any of the
transmitters,
d. a plurality of indicating devices each for indicating trouble in
a different area and identifying the area, and
e. means responsive to the receiver for selectively energizing the
indicating devices depending on the number of signals received.
Description
SUMMARY OF THE INVENTION
In the past, there have been detection and alarm systems devised
for use in connection with protection of premises such as personal
residences and industrial property against such adversities as fire
and undesirable intrusion. Usually, such systems involve the use of
detection means for sensing fire, intrusion or the like at one or
more locations on the protection property together with means at
some convenient location, usually remote from the detection zone,
for indicating detection of the undesirable condition. The
detection means may take the form of visible or audible indicators,
or both, which attract attention and advise of the need for taking
appropriate action.
In view of the separation of the detection zone or zones by some
distance from the place where an alarm is sounded, there arises the
need for transmitting signals from one place to another. In some of
the prior art devices, there is a requirement for installation of
extensive wiring reaching from one or more detection places to one
or more places for indicating the trouble. Installation of entire
wiring systems involves substantial expense and inconvenience in
existing structures, as a result of which it is desirable if
installation of additional wiring can be avoided. According to the
present invention, a detection and alarm system is provided for
detecting and indicating fire or the like and adapted to make use
of existing wiring in a building or the like for transmission of
signals at carrier frequencies, usually relatively high, over the
wiring usually already in place in existing structures for the
purpose of providing the conventional 60 cycle 110 volt power. In a
preferred form of the invention a detecting and transmitting device
may be housed in a relatively small hand-sized casing adapted to be
installed adjacent an existing wall receptacle, including a plug
adapted to register with the receptacle for purposes of providing
power supply to the transmitter and for the purposes of
superimposing carrier frequencies on the existing wiring.
Similarly, a receiving and indicating device may be housed in a
small container adapted to be utilized at a remote location
adjacent another wall receptacle, where the receiving device may be
plugged into the receptacle for power supply and for receiving the
carrier signals.
In systems of the character under consideration, where electrical
systems are utilized, it is desirable to maintain some form of
supervision over the detecting and indicating system in order to
determine that it is at all times in operative condition and ready
to perform in event of the rare occurrence of the emergency
condition against which protection is to be afforded. In accordance
with the present invention, use is made of a supervisory
transmitter employed adjacent the fire alarm transmitter. Where the
fire alarm transmitter is normally deenergized and inactive except
in case of emergency, the supervisory transmitter is supplied with
power from a similar source and is normally energized and
transmitting to a supervisory receiver in the vicinity of the alarm
receiver and the arrangement is such that if the power supply
fails, the supervisory transmitter stops transmitting and the
supervisory receiver stops receiving, at which time the latter
closes a switch in circuit with a battery source for energizing a
trouble indicator to advise of problems in the circuitry. Such an
arrangement is constructed to indicate power failure at either the
supervisory transmitter or the supervisory receiver, and these are
respectively adjacent the alarm transmitter and the alarm receiver.
If desired, the supervisory transmitter may be conveniently
packaged with the alarm transmitter and the supervisory receiver
may be packaged with the alarm receiver.
In the preferred circuitry, both transmitters are energized through
relay-controlled contacts. The relay coils are connected in series
with each other, with one or more detection switches and with a
power supply provided by the existing wiring. Supervision of the
extended part of the detecting circuitry is provided by means of a
relatively large resistance at the end of the line in parallel with
one or more detection switches, and the supervisory relay coil is a
low-current coil normally energized when the resistance is in the
circuit, while the alarm relay coil is a high-current coil which is
only energized when one of the detection switches is closed to
bypass the resistance.
In a second embodiment, the supervisory control is utilized in
connection with a system adapted for use in an industrial
installation or other large building where many widely separated
detection areas are included. In installations of this type, it is
important not only to signal the occurrence of fire or other
trouble, but also to indicate the location of the problem in order
to know at once where to take appropriate action. In the past, in
multiple area detection systems, identity as to the location of the
area where trouble occurs has sometimes been provided by utilizing
transmitters and receivers for each of the different areas
operating at different frequencies, but this involves a substantial
expense where transmitters and receivers are provided for each
zone. Alternatively, prior art devices have made use of
transmitters for sending codes which have the object of identifying
the source of trouble, but the codes are complex where many areas
are involved and they often require extensive memorization of the
codes in order to identify the signals.
According to the present invention, each of the detection zones
includes a stepping relay which may be structurally similar to the
remainder of the relays so that a movable contact is adapted to
move past a plurality of stationary contacts. In each area, a
different stationary contact is wired to interrupt the relay. In
reaching the interrupted position, each relay sends a number of
identifying signals peculiar to its location. At the indicating
station, a single relay includes a movable contact adapted to sweep
past a plurality of stationary contacts each having an indicating
device identifying a different protection zone. Thus, each
transmitter sends a number of signals peculiar to its location and
the receiver identifies the source of trouble by the number of
signals received.
DRAWINGS
FIG. 1 is a wiring diagram illustrating a combined fire alarm
transmitter and supervisory transmitter according to the present
invention;
FIG. 2 is a wiring diagram illustrating a supervisory receiver used
with the transmitter of FIG. 1;
FIG. 3 is a wiring diagram illustrating an alarm receiver used with
the transmitter of FIG. 1;
FIG. 4 is a diagram illustrating another embodiment including a
combined alarm and supervisory transmission system for use in one
of the protected zones in a large industrial installation according
to the present invention; and
FIG. 5 is a diagram illustrating an alarm and supervisory receiving
system for use with the transmission system of FIG. 4.
DETAILED DESCRIPTION
Referring now to FIG. 1 in more detail, a combined alarm and
supervisory transmitter includes two similar transmitting channels,
one designated 10 for transmitting alarm signals at a frequency on
the order of 80 kc., for example, and one designated 11 for
transmitting supervisory signals at a frequency on the order of 140
kc., for example. The transmitting circuitry is adapted to be
housed in a relatively small container on the order of 2 inches
.times. 6 inches .times. 8 inches, for example. The two
transmitting channels 10 and 11 are adapted to be supplied from a
common source such as the existing wiring in a home or the like by
means of a plug 13 adapted to be inserted in a wall receptacle to
supply the primary winding of a transformer 15. The 60 cycle supply
is converted to 12 volt DC in a full wave rectifier including the
secondary of transformer 15, a pair of diodes 16 and 17 and a
polarized capacitor 19.
The positive DC signal from either end of the secondary winding of
the transformer 15 is supplied to both transmission channels. In
the alarm channel 10, the positive signal is applied to the emitter
of transistor 22 through a biasing network including capacitor 23
and resistance 25. The base of the transistor 22 has a positive DC
bias voltage applied to it at the junction of a voltage divider
including resistances 27 and 28. The base-emitter circuit includes
a series capacitor 30 and a portion of inductor 32 which has a
common core with the collector output circuit 33 and a trap circuit
35. Since the collector circuit and the base circuit are coupled
together through the common core of the inductor 32, the necessary
feedback conditions exist and the transistor 22 functions as an
oscillator. The oscillating signal developed at the collector is
coupled to an output including transformer secondary 36 which is
serially connected through capacitors 37 and 38 to the input
circuit at opposite ends of the primary of the transformer 15 as by
means of wires 39 and 40. The oscillator frequency, for example 80
kc., is therefore impressed upon the existing distribution system
in the home or the like and may be transmitted to an alarm receiver
as described hereinbelow. The channel 10 is adapted to transmit
when normally open switch contacts 1ATR2 in circuit with capacitor
30 are closed in a manner described below.
It will be seen that transmitter channel 11 is substantially
identical with channel 10 as a result of which the description will
not be repeated. The component parts are identified by like
reference numbers with prime suffixes, except that channel 11 is
adapted to transmit upon closure of normally open switch contacts
1STR2. It should be understood that the transmitter channels 10 and
11 together with power supply are substantially conventional and
may be obtained commercially.
In the alarm transmitter channel 10, the switch contacts 1ATR2 are
relay controlled by means including a coil 1ATR which is connected
in circuit with the secondary of transformer 15 by means including
wires 42 and 44. In transmitter channel 11, the switch contacts
1STR2 are relay controlled by means including a winding 1STR in
series circuit with the winding 1ATR. The two relay coils in turn
are wired in series with one or more detection switches as at 45,
connected in parallel with each other across the wires 42 and 44.
The detection switches 45 may take any conventional form such as
well-known fire detection switches, or smoke detection switches, or
intrusion switches, or in some instances it may even be desirable
to provide manually actuable switches. In parallel with the
switches 45 at the end of the extended detection circuit, there is
a relatively high-resistance 47 connected across the wires 42 and
44. In the alarm illustrated, the supervisory relay coil 1STR is a
low-current coil which is energized across the resistance 47 when
the switches 45 are open. On the other hand, the alarm relay coil
1ATR is a high-current relay which is only energized when one of
the switches 45 is closed to bypass the resistance 47. Thus, with
the alarm shown, when the plug 13 is connected with the existing
wiring, supplying power to the transmitter channels, the relay coil
1STR is normally continuously energized, closing the contacts 1STR2
so that the transmitter channel 11 is transmitting at its frequency
of 140 kc., for example.
At the same time, the energized coil 1STR also opens its normally
closed contacts 1ATR1 in circuit with a local supervisory alarm
including an audible device 48 and a visible lamp 49 connected
across a 6 -volt battery 50. The battery 50 is normally trickle
charged by means of a transformer 52 connected across input leads
13a and 13b from the plug 13, and a rectifier in circuit with the
secondary of transformer 52, including diodes 54 and 55, and a
resistor 57. So long as the power supply at 13 continues, and the
integrity of the detection system 42,44 remains intact, the coil
1STR remains energized, the contacts 1STR1 remain open and the
indicators 48 and 49 remain deenergized. In the event of loss of
power at 13, or damage in the detection system 42,44, the coil 1STR
is deenergized, the contacts 1STR1 are closed and the battery
energizes the audible indicator 48 and the visible indicator 49. It
it is desirable to disable the audible indicator 58, a manually
operable switch 59 may be opened to discontinue the noise while the
lamp remains illuminated. In order to facilitate shipment without
discharging the battery 50, the indicator circuit may include a
pin-operated switch 60 adapted to be closed when the system is put
in use by withdrawing a manually accessible pin.
In order to provide a local alarm in the event of fire or
intrusion, the alarm relay 1ATR includes normally open switch
contacts 1ATR1 in circuit with an audible indicator 62 and a
visible lamp 63 connected across the input leads 13a and 13b. When
the coil 1ATR is energized, the contacts 1ATR1 are closed to
energize the indicators 62 and 63.
In order to restore the transmission system to normal in the event
the alarm relay 1ATR has been energized, a manual reset switch 61
is provided in circuit with the coil and adapted to be opened to
deenergize both coils on putting the system into service again.
Referring now to the supervisory receiver illustrated in FIG. 2, a
plug 65 is adapted to be inserted into a wall receptacle in the
existing wiring in a home or the like at a location remote from the
transmitter illustrated in FIG. 1. The supervisory receiver
includes leads 65a and 65b from the plug 65 to the primary of a
transformer 67 which has a secondary in circuit with a full wave
rectifier including diodes 68 and 69 and capacitor 70. Through a
wire as at 72, the DC power supply maintains the emitters of a
transistor 73 and a transistor 74 at a positive potential on the
order of 12 volts. The bias is applied to the emitter of transistor
74 through a resistance-capacitance biasing network including
resistance 75 and capacitance 76. The secondary of transformer 67
includes a center tap 77 which is connected through a relay coil
SRR to the collector of transistor 73. The center tap is connected
through coil limiting resistor 78 to one end of a tank circuit
including inductor 80 and capacitor 81. A center tap 82 on the
inductor 80 is connected to the collector of transistor 74. A
smoothing capacitance 83 is connected across the DC supply.
On transmission by the supervisory transmitter channel of FIG. 1,
the signals received at the supervisory receiver of FIG. 2 through
the plug 65 are transmitted by wires 84 and 85 through capacitors
87 and 88 to the primary of a transformer 90 including a secondary
providing the inductance in the first of two stages of a parallel
resonant circuit which selectively provides a high-voltage signal
output from the primary of transformer 92 of the second stage of
the resonant circuit. Such signal is coupled to the secondary of
transformer 92 in the base circuit of transistor 74, which may be a
standard tuned collector PNP-amplifier. The base of amplifier 74 is
connected to DC-blocking capacitor 94 which is serially connected
to a current-limiting potentiometer 95 to which the coupled
resonant frequency is applied. The base of the amplifier 74 is also
connected to the junction of a voltage divider including
resistances 97 and 98. As the transistor 74 conducts, the amplified
signal is applied to the tank circuit 80,81 in its collector which
provides an alternating voltage of a frequency which is dependent
upon the values of the capacitor 81 and the capacitors 100 and 102
in the parallel resonant input circuits. The amplified signal is
coupled through a detector circuit containing diode 104 serially
connected to a parallel load including resistance 106 and capacitor
107 and applied as a negative signal to the base of transistor 73.
A negative signal on the base of transistor 73 allows it to
conduct, providing a current path through the coil SRR.
Energization of the coil SRR opens its contacts SRR1.
The relay contacts SRR1 are in series circuit with a battery 110
(for example, 6 volts) and indicators such as an audible device 111
and a visible lamp 112. Thus, when the supervisory receiver is
normally receiving, the coil SRR is energized, the contacts SRR1
are open and the indicating devices 111 and 112 are deenergized. In
the event of power failure at the supervisory transmitter or the
supervisory receiver, the coil SRR becomes deenergized, closing the
contacts SRR1 and energizing the indicators 111 and 112. If it is
desired to eliminate the noise of the audible indicator 111, such
as a bell or buzzer, the circuit through the latter may be opened
through a manually operable switch 114.
The battery 110 is preferably connected to be trickle charged
through a transformer 116 including a secondary in circuit with a
rectifier including diodes 117 and 118, and a resistance 120.
In order to prevent discharge of battery 110 during shipment, a pin
switch 121 may be provided in circuit with alarms 111 and 112 to
keep the circuit open until withdrawal of a manually accessible
pin.
Referring now to the alarm receiver of FIG. 3, it will be noted
that the receiver is similar in many respects to the supervisory
receiver of FIG. 2 as a result of which a description of the entire
circuitry will not be repeated. The similar components are
designated by similar reference numbers with a prime suffix. The
power supply to the circuit is similar in FIG. 3 to that in FIG. 2,
the high frequency input signals are applied in similar manner, and
the output of the receiver is similar in that when the circuit is
receiving signals from the alarm transmitter channel in FIG. 1, a
coil ARR is energized. In FIG. 3, energization of coil ARR is
utilized to close its normally open contacts ARR1, whereas in FIG.
2, energization of the corresponding coil was utilized to open
contacts. It should be understood that the circuit thus far
described in FIG. 3, and the corresponding portion of FIG. 2, is
substantially conventional, and may be obtained commercially.
The relay contacts ARR1 in FIG. 3 are connected in circuit with a
control relay coil CR connected across the transformer secondary,
72',77' so that when the contacts ARR1 are closed, the coil CR is
energized. Energization of the coil CR closes its normally open
contact CR1 providing a holding circuit for the coil CR which is
adapted to be broken when desired by means of a normally closed
reset switch 122 adapted to be manually operated. Energization of
the coil CR also closes normally open switch contacts CR2 in
circuit with the transformer secondary leads 72',77' and in circuit
with indicating devices including an audible indicator such as a
bell or buzzer as at 124 and a visible lamp as at 125. Thus, when
the receiver in FIG. 3 is receiving, the coil ARR is energized,
closing the contacts ARR1, energizing the coil CR, closing the
contacts CR2, and energizing the indicators 124 and 125, thereby to
indicate the occurrence of fire or intrusion.
Referring now to the embodiment of FIGS. 4 and 5, the principles of
the invention in the system of FIGS. 1-3 is incorporated in a
system for protecting a plurality of different areas in an
industrial building or apartment building, for example, and
indicating trouble at a single remote location such as a guard
office or a caretaker's office, while identifying the area of
trouble. Toward the above ends, the circuit of FIG. 4 includes an
alarm transmitter at 130 which may be similar to the alarm
transmitter channel in FIG. 1 adapted to be supplied with power
through leads 131 and 132 connected to the wiring in the building
represented by lines 133 and 134. The present system contemplates
that there will be a plurality of alarm transmitters as at 130, one
associated with each of the areas in an apartment building or
industrial plant to be protected. Similarly, each of the protected
areas will include one or more trouble indicating switches as at
136, corresponding to the switches 45 in FIG. 1, which may be fire
or smoke detection devices or intrusion sensitive devices. The
switches 136 are connected in circuit with an alarm transmitter
relay coil 2ATR adapted to be energized on closure of one or more
of the switch contacts 136. The coil 2ATR is connected in series
circuit with the switches 136 and a DC source of power represented
by the secondary of a transformer 138 in association with a
rectifier including diode 139 and capacitor 140. The primary of the
transformer 138 is supplied from the installation wiring as by
means of leads 142 and 143.
As in the system of FIGS. 1-3, the alarm relay coil 2ATR closes a
pair of normally open contacts 2ATR1 to energize a local alarm
indicator as at 145 connected across the leads 142 and 143 to
provide a local indication at the source of the trouble that there
is a problem which requires attention.
Additionally, energization of the coil 2ATR effects closure of its
normally open contacts 2ATR2 which are adapted to control
energization of the alarm transmitter 130 through the medium of a
stepping relay 147.
A separate stepping relay 147 is provided at each of the areas or
zones to be protected and the stepping relay performs the functions
of indicating trouble and identifying the source of the trouble.
More particularly, the stepping relay includes a plurality of
stationary contacts as at 148, 149 and 150 adapted to be traversed
by a rotary contact 151. The rotary contact is movable with a
rachet 152 adapted to be indexed by a pawl 153 attractable by a
relay pulse coil 155. The coil 155 is in circuit with the contacts
2ATR2 and with a source of power through wires 156 and 158 which
lead to the building wiring represented at 133 and 134. Associated
with the relay 147 is a normally closed switch 160 in the wire 156
in circuit with the coil 155, so that when the pawl 153 is in the
normal retracted position illustrated in FIG. 4, the switch is
closed to permit energization of coil 155. In operation, when the
pawl 153 is attracted by the coil 155, the switch 160 is opened,
deenergizing the coil, so that the pawl is released to return to
the retracted position where the switch 160 is again closed. In
this manner, the stepping action of the relay is self-perpetuating,
once the contacts 2ATR2 are closed, until such time as the stepping
is self-interrupted as described below.
Interruption of the stepping action of the relay is provided
through the medium of a pair of normally closed switch contacts IR1
also in the wire 156 and adapted to be controlled by an interrupt
relay coil IR. The coil IR is wired in circuit with one of the
stationary switch contacts 149 and to the supply line 134 through a
lead 162. A circuit is adapted to be completed through the coil IR
when the movable contact 151 reaches the stationary contact 150 in
circuit with the coil. The center of the movable contact 151 is
connected to the other supply line 133 through a lead 163. In
operation, when the movable contact 151 causes energization of the
coil IR, the contacts IR1 are opened and the stepping action of the
relay is interrupted even though the switch 160 is closed. As will
appear more clearly hereinbelow, the various stepping relays 147 in
the different detection areas each have a different one of the
stationary contacts 148, 149, 150 wired in circuit with a coil as
at IR, as a result of which each of the stepping relays is adapted
to index a predetermined number of steps, one or more, and stop,
but the number of steps in each relay is different. In this manner,
similar relay constructions may be used in each of the areas merely
by wiring the coil IR to a different stationary contact in each
area, and the relays serve to identify the source of the signal
indicating trouble.
In order to control the alarm transmitter 130 on actuation of the
stepping relay 147, the alarm transmitter includes a pair of wires
as at 165 in circuit with a normally open switch 167 adapted to
control energization of the transmitter on closure of the switch.
That is, the switch 167 functions to energize the transmitter in
the same manner that the switch 1ATR2 energizes the alarm
transmitter channel in FIG. 1. The switch 167 is arranged for
control by the stepping relay 147 so that each time the pawl 153 is
attracted by the coil 155, the switch 167 is closed to energize the
alarm transmitter. On each energization, the alarm transmitter
sends a short signal. The number of signals sent by the alarm
transmitter corresponds to the number of closures of the switch 167
which in turn corresponds with the number of steps the movable
contact 151 is indexed, and of course the latter number differs in
each area of detection.
Referring to FIG. 5, at an appropriate control station, there is a
single alarm receiver as at 170 which may correspond substantially
with the alarm receiver illustrated in FIG. 3. The receiver 170 is
connected by wires 171 and 172 to the existing wiring as at 133 and
134 so that the latter supplies power for the receiver and also
provides the medium by which carrier signals are transmitted from
the alarm transmitter 130 to the alarm receiver 170. The output
from the receiver 170 includes a pair of wires as at 174 and 175
connected in circuit with a switch in the receiver corresponding to
the normally open switch ARR1 in FIG. 3 so that when the receiver
is receiving, the switch is closed, and a circuit may be made
through the wires 174 and 175, the former of which is connected to
the existing wiring as at 134, and the latter of which leads to a
relay pulse coil 177 in turn connected by wire 178 to the existing
wiring 133. In this manner, each short signal burst at the receiver
170 results in a pulse applied to the coil 177.
The coil 177 attracts an indexing pawl 180 in a stepping relay 181
including a ratchet 182 indexed by the pawl 180 and rotatable with
a movable switch contact 183 adapted to wipe across a plurality of
stationary contacts as at 184, 185 and 186, for example. The center
tap of the movable contact 183 is connected by a wire 188 to the
existing wiring as at 133. The movable contact is adapted to
complete a circuit through each of the stationary contacts, each of
which is wired through a different lamp as at 190, 191 and 192, for
example, in turn connected with the existing wiring as at 134. Each
of the lamps corresponds to a different detection area. For
example, let it be assumed that in connection with a detection area
A, the first stationary contact 148 in the transmitter stepper
relay would be wired to an interrupt coil IR. As a result, the
detection of trouble in area A would result in indexing of movable
contact 151 in the transmitter stepper a single step and indexing
of the movable contact 183 in the receiver stepper relay a single
step to thereby energize lamp 190, indicating trouble in area A.
Similarly, if stationary contact 149 in FIG. 4 is wired to
interrupt coil IR, the movable contact 183 in FIG. 5 will be
indexed two steps to energize lamp B. In area C, if stationary
contact 150 is wired to coil IR, movable contact 183 will index
three steps and stop at stationary contact 186 to energize lamp 192
indicating trouble in area C.
As the system is operated, with the pawl 153 in FIG. 4 indexing the
ratchet 152, the latter is spring biased toward the home or
starting position and is retained at each indexed position by means
such as a retention pawl 194. After operation of the system, when
it is desired to put it back into use, the stepper relay may be
reset by means of a reset coil 196 adapted to attract the retention
pawl 194, allowing return of the rachet 152 to the home position.
The coil 196 may be wired across the lines 133 and 134 through a
normally open pushbutton reset switch 198.
In similar manner, the rachet 182 in FIG. 5 may be biased toward
the home or starting position and held in indexed positions by
means of retention pawl 200 adapted to be withdrawn for reset by
energization of a coil 202 energizable through a normally open
reset switch 204.
Supervision of the system thus far described in FIGS. 4 and 5 is
preferably provided by a single supervisory transmitter as at 210
which may be similar to the supervisory transmitter channel 11 in
FIG. 1 and connected to the house wiring 133, 134 as by wires 211
and 212 which provide a power supply to the transmitter and provide
the vehicle by which the supervisory transmitter signals are
applied to the wiring 133, 134. In order to provide appropriate
supervision, the transmitter 210 is associated with the alarm
transmitter 130 located at the most remote detection area so as to
be capable of determining the loss of power or a line break at any
place between the source of power and the end of the extension
system most remote from the source of power. Energization of the
transmitter 210 is controlled by normally open relay switch
contacts 2STR2 in circuit with the transmitter through leads 215
and 216. The switch 2STR2 corresponds with that shown at 1STR2 in
the supervisory transmitter channel in FIG. 1. The normally open
contacts 2STR2 are adapted to be controlled by a supervisory
transmitter relay winding 2STR in circuit with the alarm relay
winding 2ATR at the most remote detection area.
As in the system of FIG. 1, the circuit including the windings 2ATR
and 2STR also has a relatively high resistance as at 218 in
parallel with the detection switches 136 so that when the latter
are open, there is normally a low-current high-resistance circuit
adapted to energize the supervisory winding 2STR while leaving the
alarm winding 2ATR deenergized. Energization of the winding 2STR
closes the contacts 2STR2 so that the supervisory transmitter 210
is normally transmitting as in FIG. 1. At the same time,
energization of the coil 2STR opens the normally closed contacts
2STR1 preventing energization of trouble indicators such as visible
lamp 220 and audible bell 221, in circuit with the contacts 2STR1
and a battery 222. So long as the power supply is operative, the
battery is trickle charged by means of a rectifier 225 which may be
connected with leads 142 and 143.
In event of power failure in the most remote detection area or at
any detection area between the most remote and the source of power
supply to the house, the winding 2STR is deenergized, closing
contacts 2STR1, energizing the indicators 220 and 221. The noise of
the latter may be discontinued if desired by opening a manual
switch 227.
In operation, the supervisory transmitter 210 supplies signals at a
frequency adapted to be received by a supervisory receiver as at
230 (FIG. 5) corresponding substantially to that illustrated in
FIG. 2 and adapted to be connected to the house wiring by leads 231
and 232 which provide power supply and transmit carrier signals to
the receiver. The receiver includes internally a switch
corresponding to that at SRR1 in FIG. 2 adapted to be held open as
long as the receiver is receiving. On failure to receive, the
switch closes to complete a circuit from a battery 233 to audible
indicator 234 and visible indicator 235, the former of which may be
silenced by opening manual switch 236. The battery is trickle
charged through a rectifier 237 connected across the house
wiring.
It will be understood that in all the detection areas but the most
remote the supervisory transmitter will be omitted and the controls
associated with it will be unnecessary.
In order to restore the system of FIG. 4 to normal after
energization of alarm relay 2ATR, a manual reset switch 238 is
provided in circuit with the coils 2ATR and 2STR to be opened to
deenergize both coils for putting the system into service
again.
* * * * *