CA1244533A - Flood detector - Google Patents
Flood detectorInfo
- Publication number
- CA1244533A CA1244533A CA000529148A CA529148A CA1244533A CA 1244533 A CA1244533 A CA 1244533A CA 000529148 A CA000529148 A CA 000529148A CA 529148 A CA529148 A CA 529148A CA 1244533 A CA1244533 A CA 1244533A
- Authority
- CA
- Canada
- Prior art keywords
- pair
- electrodes
- insulating jacket
- stripping
- conductive
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B21/00—Alarms responsive to a single specified undesired or abnormal condition and not otherwise provided for
- G08B21/18—Status alarms
- G08B21/182—Level alarms, e.g. alarms responsive to variables exceeding a threshold
Landscapes
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Emergency Alarm Devices (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A flood alarm system comprising a plurality of sensor means to detect the presence of water or other conductive fluids in an open space is disclosed. Sensor means comprising exposed electrodes formed from parallel conductive pairs and encased in perforated cover means are effective when in the presence of conductive fluid to close a circuit and enable an indicator means and to bias on a driver means for sounding an alarm.
A flood alarm system comprising a plurality of sensor means to detect the presence of water or other conductive fluids in an open space is disclosed. Sensor means comprising exposed electrodes formed from parallel conductive pairs and encased in perforated cover means are effective when in the presence of conductive fluid to close a circuit and enable an indicator means and to bias on a driver means for sounding an alarm.
Description
This invention yenerally relates to an electrically operated alarm which uses conductive fluid activated sensors to detect the presence oE a conductive fluid in an open area to trigger an audio and visual alarm.
B GROUND OF T~E INVENTION
Many people have had the said experience of having their basement or part of their business or commercial facilities flooded (usually by water), often with significant damage. The causes of such misfortune are numerous: faulty washing machine, faulty water tank, broken pipes, broken city water main, torrential rain, failure of a sump pump, spring melt down, river overflow, etc. Quite often measures could have been taken to eliminate the cause or least to minimize the damages. The flood alarm system described herein is a battery lor power adaptor) operated device which uses conduc-tive fluid activated sensors to trigger a visual and audio alarm. The device can also be used to transmit the alarm to a remote position or/and to another alarm such as a cable monitored burglar alarm. This alarm will inform the user of the flood alarm system that a conductive fluid is present in the position of one or more of the sensors. The user could then immediately initiate corrective action to stop the cause of the flooding and minimize damage. The device is simple, easy to install and inexpensive. It would thus be available to tne public at large. It would see use in residential and commercial buildings to warn the occupants of flooding and could see numerous secondary applications such as in small boats to indicate that the water level has reached a given point, or to indicate that a septic tank ls full.
Q~
-- 2 ~ J L~ ~k 5 3 3 There are a number o~ patented devices using the principle of fluid conductivity to close a circuit between two exposed electrodes. Most of the devices are intended to indicate the level of a given fluid, the presence of impurities in a fluid, a change in Eluid density, etc. Most of the patented devices are designed to operate in some form of container in mechanical, chemical and other processes. These prior devices are generally unsuitable to detect the presence of fluids in open spaces such as the basement of a house. Furthermore, most of these devices use standard electrical power to operate. ~his can prove inconvenient in the case of a power failure which cause such devices to fail to operate, a problem commonly encountered with other electrically powered devices such as sump pumps.
In accordance with the present invention, there is provided an inexpensive and easy to install alarm device effective to warn that flooding has begun in the location monitored. In response to the warning, action can be taken immediately by the user to minimize the hardships, damage and the insurance claims normally associated with Elooding.
In accordance with one aspect of the present invention there is provided a sensor means for detecting the presence of conductive fluid in an open area comprising an electrically conductive pair, at least one pair of exposed electrodes in closely spaced relation, each of said electrodes connected to a different conductor of said conductive pair, at least one cover means, each cover means enclosing one pair of said electrodes, said cover means including at least one opening to allow ingress of conductive fluid into said cover means.
_ 3 _ ~ 533 In accordance with another aspect of the invention, there is provided a flood alarm system comprising a power supply, at least one detection circuit and an alarm circuit, each of said detection circuits connected between the first and second terminals of said power supply and comprising in series an indicator means and a sensor means responsive to the presence of conductive fluid to close a current path through said detection circuit and enable said indicator means, said alarm circuit connected between the first and second terminals of said power supply and comprising in series an alarm means and a driver means, said driver means connected to each of said detection circuits for deriving a source of bias voltage when any one of said detection circuits is closed, said sensor means comprising an electrically conductive pair, at least one pair of exposed electrodes in closely spaced relation, each of said electrodes connected to a different conductor of said conductive pair, at least one cover means, each cover means enclosing one pair of said electrodes, said cover means including at least one opening to allow ingress of conductive fluid into said cover means.
BRIEF DESCRIPTION OF THE DRAWINGS
In drawings which illustrate embodiments of the invention:
Figure 1 is a schematic representation of the main flood alarm system components.
Figure 2 is a perspective drawing showing details of a first conductive fluid sensor means.
Figure 3 is a perspective drawing showing details of a second conductive fluid sensor means.
Figure 4 is a drawing of a conductive fluid sensor Means having five exposed electrode pairs.
Figure 5 is a circuit diagram of the flood alarm system circuit.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The general layout of the main components of the flood alarm system is shown in Figure 1. The flood detector unit can be connected to an alternate battery power source to ensure operation when electrical service fails. Point and area sensors are connected to the flood detector unit and are placed by the user in the open area in which the presence of water or other conductive fluid is to be monitored, such as for example in a basement. When one or more of the sensors are placed in contact with water or other conductive fluid, an alarm circuit is made in the flood detector unit soundiny an audible alarm. A remote buzzer can be used to alert the user at a location remote from the flood detector unit, such as for example in an upstairs bedroom. Upon being alerted, the user would go to the location of the flood detector unit and inspect the indicator lights located on the flood detector unit which indicate which of the sensors are in contact with water or other conductive fluid.
Knowing the location of the floodin~, the user can then take remedial action. The flood detector can also be connected to a remote alarm system, such as for example a cable connected subscription security system to enable flood monitoring to be carried out in the user's absence.
The basic circuit of the flood alarm system is depicted in Figure 5. Power is applied at points A and B by an external power source such as a 9 vo:lt AC/DC adaptor. Back up battery C
_ 5 _ ~2~53~
operates in conjunction with diodes D to provide power in case of failure of the external power source. Four sirnilar detection circuits are shown connected in parallel between power supply terminals A and B. Each detection circuit includes normally closed manual switch E, indicator light F and a conductive fluid sensor having at least one exposed electrode pair. For illustration, the four detection circuits shown in Figure 5 each have one of exposed electrode pairs OP, QR, ST and UV. When a conductive fluid such as water bridges the gap between electrodes O and P, for example, a current path through the indicator circuit is closed. The flow of current causes indicator light F
to glow indicating which conductive fluid sensor is in the presence of conductive fluid. The indicator light F is preferably a light emitting diode. Because light emitting diodes require very little current to operate, they can be enabled by the small current which typically passes between exposed electrodes when in the presence of water, a relatively poor conductor of electricity.
The flood alarm system is also provided with an alarm circuit.
The alarm ci~cuit is connected between the power supply terminals A and B and includes alarm buzzer I and transistor driver L.
When one or more of the detection circuits is closed due to conductive fluid between one or more of the electrode pairs OP, QR, ST and UV, a bias voltage is applied to the base of transistor driver L through resistors M and N causing transistor driver L to conduct, thereby sounding alarm buzzer I which typically has a high current demand. Remote alarm buzzer J can be connected in parallel with alarm buzzer I to sound an alarm to a remote location. Remote alarm buzzer J allows the user to position the flood detector unit in the basement and the remote ~ 6 - ~2~4S33 alarm buzzer J in an office or a bedroom or a different floor.
In addition, a cable connected subscription security system could be connected at point K. The cable connected system could use the change in voltage at point K upon actuation of alarm buzzer I to trigger the subscription alarm system.
When the alarm buzzer I is sounded, the user can inspect indicator lights F to determine which conductive fluid sensor i5 in the presence of conductive fluid. The user can stop alarm buzzer I by opening manual switch E thereby removing the bias voltage from transistor driver L.
The flood alarm system circuit depicted in Figure 5 also includes a test circuit comprising normally open manual switch G and test indicator light H. Pressing switch G will activate test indicator light H and will sound alarm buzzer I and, if connected, remote buzzer J.
A conductive fluid sensor in accordance with the present invention is shown in Figure ~. The sensor comprises an electrically conductive pair, and a plurality of exposed electrode pairs, each enclosed in a cover means. The cover means
B GROUND OF T~E INVENTION
Many people have had the said experience of having their basement or part of their business or commercial facilities flooded (usually by water), often with significant damage. The causes of such misfortune are numerous: faulty washing machine, faulty water tank, broken pipes, broken city water main, torrential rain, failure of a sump pump, spring melt down, river overflow, etc. Quite often measures could have been taken to eliminate the cause or least to minimize the damages. The flood alarm system described herein is a battery lor power adaptor) operated device which uses conduc-tive fluid activated sensors to trigger a visual and audio alarm. The device can also be used to transmit the alarm to a remote position or/and to another alarm such as a cable monitored burglar alarm. This alarm will inform the user of the flood alarm system that a conductive fluid is present in the position of one or more of the sensors. The user could then immediately initiate corrective action to stop the cause of the flooding and minimize damage. The device is simple, easy to install and inexpensive. It would thus be available to tne public at large. It would see use in residential and commercial buildings to warn the occupants of flooding and could see numerous secondary applications such as in small boats to indicate that the water level has reached a given point, or to indicate that a septic tank ls full.
Q~
-- 2 ~ J L~ ~k 5 3 3 There are a number o~ patented devices using the principle of fluid conductivity to close a circuit between two exposed electrodes. Most of the devices are intended to indicate the level of a given fluid, the presence of impurities in a fluid, a change in Eluid density, etc. Most of the patented devices are designed to operate in some form of container in mechanical, chemical and other processes. These prior devices are generally unsuitable to detect the presence of fluids in open spaces such as the basement of a house. Furthermore, most of these devices use standard electrical power to operate. ~his can prove inconvenient in the case of a power failure which cause such devices to fail to operate, a problem commonly encountered with other electrically powered devices such as sump pumps.
In accordance with the present invention, there is provided an inexpensive and easy to install alarm device effective to warn that flooding has begun in the location monitored. In response to the warning, action can be taken immediately by the user to minimize the hardships, damage and the insurance claims normally associated with Elooding.
In accordance with one aspect of the present invention there is provided a sensor means for detecting the presence of conductive fluid in an open area comprising an electrically conductive pair, at least one pair of exposed electrodes in closely spaced relation, each of said electrodes connected to a different conductor of said conductive pair, at least one cover means, each cover means enclosing one pair of said electrodes, said cover means including at least one opening to allow ingress of conductive fluid into said cover means.
_ 3 _ ~ 533 In accordance with another aspect of the invention, there is provided a flood alarm system comprising a power supply, at least one detection circuit and an alarm circuit, each of said detection circuits connected between the first and second terminals of said power supply and comprising in series an indicator means and a sensor means responsive to the presence of conductive fluid to close a current path through said detection circuit and enable said indicator means, said alarm circuit connected between the first and second terminals of said power supply and comprising in series an alarm means and a driver means, said driver means connected to each of said detection circuits for deriving a source of bias voltage when any one of said detection circuits is closed, said sensor means comprising an electrically conductive pair, at least one pair of exposed electrodes in closely spaced relation, each of said electrodes connected to a different conductor of said conductive pair, at least one cover means, each cover means enclosing one pair of said electrodes, said cover means including at least one opening to allow ingress of conductive fluid into said cover means.
BRIEF DESCRIPTION OF THE DRAWINGS
In drawings which illustrate embodiments of the invention:
Figure 1 is a schematic representation of the main flood alarm system components.
Figure 2 is a perspective drawing showing details of a first conductive fluid sensor means.
Figure 3 is a perspective drawing showing details of a second conductive fluid sensor means.
Figure 4 is a drawing of a conductive fluid sensor Means having five exposed electrode pairs.
Figure 5 is a circuit diagram of the flood alarm system circuit.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The general layout of the main components of the flood alarm system is shown in Figure 1. The flood detector unit can be connected to an alternate battery power source to ensure operation when electrical service fails. Point and area sensors are connected to the flood detector unit and are placed by the user in the open area in which the presence of water or other conductive fluid is to be monitored, such as for example in a basement. When one or more of the sensors are placed in contact with water or other conductive fluid, an alarm circuit is made in the flood detector unit soundiny an audible alarm. A remote buzzer can be used to alert the user at a location remote from the flood detector unit, such as for example in an upstairs bedroom. Upon being alerted, the user would go to the location of the flood detector unit and inspect the indicator lights located on the flood detector unit which indicate which of the sensors are in contact with water or other conductive fluid.
Knowing the location of the floodin~, the user can then take remedial action. The flood detector can also be connected to a remote alarm system, such as for example a cable connected subscription security system to enable flood monitoring to be carried out in the user's absence.
The basic circuit of the flood alarm system is depicted in Figure 5. Power is applied at points A and B by an external power source such as a 9 vo:lt AC/DC adaptor. Back up battery C
_ 5 _ ~2~53~
operates in conjunction with diodes D to provide power in case of failure of the external power source. Four sirnilar detection circuits are shown connected in parallel between power supply terminals A and B. Each detection circuit includes normally closed manual switch E, indicator light F and a conductive fluid sensor having at least one exposed electrode pair. For illustration, the four detection circuits shown in Figure 5 each have one of exposed electrode pairs OP, QR, ST and UV. When a conductive fluid such as water bridges the gap between electrodes O and P, for example, a current path through the indicator circuit is closed. The flow of current causes indicator light F
to glow indicating which conductive fluid sensor is in the presence of conductive fluid. The indicator light F is preferably a light emitting diode. Because light emitting diodes require very little current to operate, they can be enabled by the small current which typically passes between exposed electrodes when in the presence of water, a relatively poor conductor of electricity.
The flood alarm system is also provided with an alarm circuit.
The alarm ci~cuit is connected between the power supply terminals A and B and includes alarm buzzer I and transistor driver L.
When one or more of the detection circuits is closed due to conductive fluid between one or more of the electrode pairs OP, QR, ST and UV, a bias voltage is applied to the base of transistor driver L through resistors M and N causing transistor driver L to conduct, thereby sounding alarm buzzer I which typically has a high current demand. Remote alarm buzzer J can be connected in parallel with alarm buzzer I to sound an alarm to a remote location. Remote alarm buzzer J allows the user to position the flood detector unit in the basement and the remote ~ 6 - ~2~4S33 alarm buzzer J in an office or a bedroom or a different floor.
In addition, a cable connected subscription security system could be connected at point K. The cable connected system could use the change in voltage at point K upon actuation of alarm buzzer I to trigger the subscription alarm system.
When the alarm buzzer I is sounded, the user can inspect indicator lights F to determine which conductive fluid sensor i5 in the presence of conductive fluid. The user can stop alarm buzzer I by opening manual switch E thereby removing the bias voltage from transistor driver L.
The flood alarm system circuit depicted in Figure 5 also includes a test circuit comprising normally open manual switch G and test indicator light H. Pressing switch G will activate test indicator light H and will sound alarm buzzer I and, if connected, remote buzzer J.
A conductive fluid sensor in accordance with the present invention is shown in Figure ~. The sensor comprises an electrically conductive pair, and a plurality of exposed electrode pairs, each enclosed in a cover means. The cover means
2~ with its lid removed is shown in greater detail in Figures 2 and
3. The electrically conductive pairs comprise parallel conductive wires encased in a unitary insulating jacket. The exposed electrodes are formed by stripping a portion of unitary insulating jacket thereby exposing adjacent portions of the conductive wires. Non conductive spacers represented in Figure in black are connected to or are formed integrally with the cover means and serve to maintain the exposed electrodes in closely spaced relation without touching. The cover means can be - 7 - ~ ~4~S~3 made of plastic or other suitable material and is provided with one or more perforations to allow ingress of conductive fluid into the cover means. The cover means protects each exposed electrode pair from dirt, debris, damage and accidental touching.
When conductive fluid bridges the small gap between the exposed electrodes, the wires of the electrically conductive pair are placed in electrical communication allowing the conductive pair to be used to trigger an indicator and/or alarm. The exposed electrodes should be sufficiently long to allow adequate current -to energize or enable the indicator or alarm.
The exposed electrodes shown in Figure 2 are particularly suited to be used in the vertical position for detecting a rise in the level of conductive fluid passed a given threshold. The ends of the exposed electrodes are bent to be parallel with the surface of the water body the height of which is being monitored.
Accordingly, as soon as the water level makes initial contact with the hori~ontal portion of the bent electrodes, there is a sufficiently large wetted areas to pass adequate current to energize or enable the indicator or alarm.
- Although meant to serve as a flood alarm system for residential and commerical buildings, the device could be also economically used in many areas such as in sma~l ships to indicate that water has reached a certain level by positioning the sensors accordingly. It could also indicate the rise of any body of water which might endanger installations. It could also indicate the failure of a pump by placing a sensor at a point higher than that at which the level of a fluid would have started the pump~
There are indeed numerous applications which would benefit the public.
When conductive fluid bridges the small gap between the exposed electrodes, the wires of the electrically conductive pair are placed in electrical communication allowing the conductive pair to be used to trigger an indicator and/or alarm. The exposed electrodes should be sufficiently long to allow adequate current -to energize or enable the indicator or alarm.
The exposed electrodes shown in Figure 2 are particularly suited to be used in the vertical position for detecting a rise in the level of conductive fluid passed a given threshold. The ends of the exposed electrodes are bent to be parallel with the surface of the water body the height of which is being monitored.
Accordingly, as soon as the water level makes initial contact with the hori~ontal portion of the bent electrodes, there is a sufficiently large wetted areas to pass adequate current to energize or enable the indicator or alarm.
- Although meant to serve as a flood alarm system for residential and commerical buildings, the device could be also economically used in many areas such as in sma~l ships to indicate that water has reached a certain level by positioning the sensors accordingly. It could also indicate the rise of any body of water which might endanger installations. It could also indicate the failure of a pump by placing a sensor at a point higher than that at which the level of a fluid would have started the pump~
There are indeed numerous applications which would benefit the public.
Claims (16)
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:-
1. A sensor means for detecting the presence of a conductive fluid in an open area comprising an electrically conductive pair, at least one pair of exposed electrodes in closely spaced relation, each of said electrodes connected to a different conductor of said conductive pair, at least one cover means, each cover means enclosing one pair of said electrodes, said cover means including at least one opening to allow ingress of conductive fluid into said cover means.
2. A sensor means according to claim 1 wherein said electrically conductive pair comprises two parallel conductive wires encased in a unitary insulating jacket, each pair of said electrodes formed by stripping a portion of said insulating jacket thereby exposing adjacent portions of said wires.
3. A sensor means according to claim 2 wherein one pair of said electrodes is formed by stripping the end portion of said insulating jacket.
4. A sensor means according to claim 2 wherein at least one pair of said electrodes is formed by stripping a portion of said insulating jacket intermediate its ends.
5. A sensor means according to claim 2 wherein one pair of said electrodes is formed by stripping the end portion of said insulating jacket and at least one pair of said electrodes is formed by stripping a portion of said insulating jacket intermediate its ends.
6. A sensor means according to claims 3, 4 or 5 including spacer means connected to said cover means for maintaining the electrodes of each said electrode pair in closely spaced relation.
7. A sensor means according to claim 3 wherein each electrode of said pair of electrodes is bent in a direction parallel to the surface of the conductive fluid the presence of which is being detected.
8. A flood alarm system comprising a power supply, at least one detection circuit and an alarm circuit, each of said detection circuits connected between the first and second terminals of said power supply and comprising in series in indicator means and a sensor means responsive to the presence of conductive fluid to close a current path through said detection circuit and enable said indicator means, said alarm circuit connected between the first and second terminals of said power supply and comprising in series an alarm means and a driver means, said driver means connected to each of said detection circuits for deriving a source of bias voltage when any one of the said detection circuits is closed, said sensor means comprising an electrically conductive pair, at least one pair of exposed electrodes in closely spaced relation, each of said electrodes connected to a different conductor of said conductive pair, at least one cover means, each cover means enclosing one pair of said electrodes, said cover means including at least one opening to allow ingress of conductive fluid into said cover means.
9. A flood alarm system according to claim 8 wherein said indicator means is a light emitting diode.
10. A flood alarm system according to claim 8 wherein said driver means is a transistor.
11. A flood alarm system according to claim 8 wherein said electrically conductive pair comprises two parallel conductive wires encased in a unitary insulating jacket, each pair of said electrodes formed by stripping a portion of said insulating jacket thereby exposing adjacent portions of said conductive wires.
12. A flood alarm system according to claim 8 wherein one pair of said electrodes is formed by stripping the end portion of said insulating jacket.
13. A flood alarm system according to claim 8 wherein at least one pair of said electrodes is formed by stripping a portion of said insulating jacket intermediate its ends.
14. A flood alarm system according to claim 8 wherein one pair of said electrodes is formed by stripping the end portion of said insulating jacket and at least one pair of said electrodes is formed by stripping a portion of said insulating jacket intermediate its ends.
15. A flood alarm system according to claims 12, 13 and 14 including spacer means connected to said cover means for maintaining the electrodes of each said electrode pair in closely spaced relation.
16. A flood alarm system according to claim 13 wherein each electrode of said pair of electrodes is bent in a direction parallel to the surface of the conductive fluid the presence of which is being detected.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000529148A CA1244533A (en) | 1987-02-06 | 1987-02-06 | Flood detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000529148A CA1244533A (en) | 1987-02-06 | 1987-02-06 | Flood detector |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1244533A true CA1244533A (en) | 1988-11-08 |
Family
ID=4134919
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000529148A Expired CA1244533A (en) | 1987-02-06 | 1987-02-06 | Flood detector |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1244533A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2700871A1 (en) * | 1993-01-28 | 1994-07-29 | Roger Jean Michel | Traffic lights for a coastal roadway liable to flooding |
| US5458766A (en) * | 1992-09-14 | 1995-10-17 | Yuasa Corporation | Life indicator and cartridge for indicating total water flow |
-
1987
- 1987-02-06 CA CA000529148A patent/CA1244533A/en not_active Expired
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5458766A (en) * | 1992-09-14 | 1995-10-17 | Yuasa Corporation | Life indicator and cartridge for indicating total water flow |
| FR2700871A1 (en) * | 1993-01-28 | 1994-07-29 | Roger Jean Michel | Traffic lights for a coastal roadway liable to flooding |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |