WO2000058753A1 - Systeme d'alarme ameliore pour piscine - Google Patents

Systeme d'alarme ameliore pour piscine Download PDF

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Publication number
WO2000058753A1
WO2000058753A1 PCT/AU2000/000262 AU0000262W WO0058753A1 WO 2000058753 A1 WO2000058753 A1 WO 2000058753A1 AU 0000262 W AU0000262 W AU 0000262W WO 0058753 A1 WO0058753 A1 WO 0058753A1
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WO
WIPO (PCT)
Prior art keywords
bodies
fish
detecting
acoustic energy
liquid
Prior art date
Application number
PCT/AU2000/000262
Other languages
English (en)
Inventor
Lance Duke
Original Assignee
Kmr Concepts Pty Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Kmr Concepts Pty Ltd filed Critical Kmr Concepts Pty Ltd
Priority to AU34089/00A priority Critical patent/AU3408900A/en
Publication of WO2000058753A1 publication Critical patent/WO2000058753A1/fr

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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
    • G08B21/02—Alarms for ensuring the safety of persons
    • G08B21/08—Alarms for ensuring the safety of persons responsive to the presence of persons in a body of water, e.g. a swimming pool; responsive to an abnormal condition of a body of water
    • G08B21/082—Alarms for ensuring the safety of persons responsive to the presence of persons in a body of water, e.g. a swimming pool; responsive to an abnormal condition of a body of water by monitoring electrical characteristics of the water
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
    • G01S15/02—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems using reflection of acoustic waves
    • G01S15/04—Systems determining presence of a target

Definitions

  • the present invention relates to alarms, and more particularly, to alarms used for detecting the presence of living creatures such as small children, birds or animals in unattended bodies of water such as swimming pools.
  • Unattended bodies of water such as swimming pools, dams, spas and the like present serious safety hazards to young children, birds and animals.
  • a disturbing number of young children die every year through drowning, many in their own backyard pools.
  • parents have returned after taking a quick phone call, or after leaving their children temporarily unattended for matter of seconds, to find that tragedy has struck.
  • the first type of known pool alarn system which relies on the water displacement method, generally employs monitoring apparatus for detecting an unauthorised or accidental intrusion into a pool based on a change in water level.
  • Such systems often use some form of hydraulic cavity which is partially filled with water and which indicates the average water level of the pool.
  • the cavity usually has an upper frequency cut-off point which is low enough so that the alarm is not set off by wind generated surface wave action or sudden disturbances.
  • the hydraulic cavity is a resonant cavity. The change in its resonant frequency is detected and, if the change is above some threshold level, an alarm will be sounded.
  • the second type of known pool alarm system detects underwater wave motion.
  • Such systems are designed to pick up any transient wave motion caused by the entry of an object into a pool.
  • One disadvantage of this method is that the apparatus is dependent upon transient wave motion and can therefore fail to detect a child sliding smoothly into the pool, causing little or no transient wave motion.
  • a second disadvantage of this system is that it is liable to false tripping when high winds or tree branches fall into the pool and cause transient wave motion.
  • Modified hydrophone, transient wave detection systems of the prior art include those having a long tube which is vertically immersed in the swimming pool leaving a small air cavity at the top of the tube.
  • the movement of waves underwater causes the air pressure in the air cavity to fluctuate.
  • This fluctuation is commonly detected by a piezoelectric device, which converts it to an electrical signal .
  • This electrical signal is then amplified and compared to a predetermined threshold value. If the signal exceeds this threshold, an alarm is activated.
  • a disadvantage of this system is that it may not detect the sliding intrusion of a person into a pool which does not cause a significant submarine wave front. Furthermore, a very small child may not cause enough wave motion to set the alarm off.
  • the third type of known pool alarm system is based on the detection of a change in amplitude of a sound wave emitted by one transducer and received by another.
  • One device for example, uses a plurality of transmitters and receivers arranged in a grid-like fashion across all sides of the pool such that each transmitter sequentially signals its corresponding receiver to establish a detection plane. An object entering this detection plane will block or decrease the signal exchanged between one of the transmitter- receiver pairs. Such a blockage or decrease in sound wave signal sets off the alarm. Whilst such systems do not rely on the intruding object generating transient wave motion, such systems have the disadvantage of being rather expensive. This is due to the large number of transmitter- receiver pairs needed for the device to function properly. In addition, such systems will be set off by any type of object entering the pool and are therefore susceptible to false tripping.
  • the fourth type of pool alarm system which detects a change in the speed of return of an acoustic energy pulse received at a transducer goes some way towards overcoming the problems of the prior art.
  • One example of this system uses transducers which generate acoustic energy pulses at certain time intervals. These time intervals are large enough so that a pulse sent out from a transducer has time to echo off the walls of the pool and return to the transducer before the next pulse is omitted. A normal travel time value is therefore established for the transmission of the acoustic energy in the pool when no foreign bodies are present.
  • the reflected echoes are compared to this normal travel time and, if a reflected echo has a shorter travel time than the normal travel time, this indicates that a foreign body is in the pool and the alarm is set off. This therefore relies only on the time of return of an acoustic pulse.
  • One disadvantage of this system is that it is liable to false tripping when any type of object enters the pool. The alarm will be set off if a branch, pool chair, brick, child or any other object falls into the pool. Owners of such a system having small children may be unnecessarily distressed by an alarm going off when only a branch, or some large leaves have fallen into the pool.
  • a second disadvantage is that such a system may not be used in conjunction with a "Creepy-Crawlie" or similar pool cleaning device.
  • Such pool cleaning devices use an automatic suction device which travels around the pool of its own accord.
  • a pool alarm which only detects the difference in return time of echoes will inevitably be set off by such pool cleaning systems. As a result, either the alarm will need to be turned off, presenting the usual dangers for small children and animals, or the pool will need to remain uncleaned.
  • a system for detecting the presence of living creatures other than fish in bodies of liquid including: transmitting means positioned within the body of liquid for transmitting acoustic energy through the body of liquid; receiving means positioned within the body of liquid for receiving reflected acoustic energy; wherein at least part of the reflected acoustic energy received by said receiving means is compared with at least one reflected acoustic energy reference and an alarm activation signal is created if at least part of said reflected acoustic energy corresponds at least partially to at least one living creature reflected acoustic energy reference.
  • said living creature reflected acoustic energy reference is characterised by a central region of little or no acoustic energy, corresponding to the air inside the living creature.
  • a system for detecting the presence of living creatures other than fish in bodies of liquid substantially as described above wherein said acoustic energy includes an acoustic wave and is preferably at least one supersonic acoustic wave.
  • a system for detecting the presence of living creatures other than fish in bodies of liquid substantially as described above wherein said transmitting means preferably includes at least one transmitting transducer.
  • a system for detecting the presence of living creatures other than fish in bodies of liquid substantially as described above wherein said receiving means preferably includes at least one receiving transducer.
  • a system for detecting the presence of living creatures other than fish in bodies of liquid substantially as described above wherein said transmitting and receiving means preferably take the form of at least one transducer capable of both transmitting and receiving acoustic energy including supersonic acoustic waves.
  • a system for detecting the presence of living creatures other than fish in bodies of liquid substantially as described above further including storage means and comparing means for storing at least one reflected acoustic energy reference and comparing same with said reflected acoustic energy.
  • a system for detecting the presence of living creatures other than fish in bodies of liquid substantially as described above further including alarm means wherein the alarm means is activated when it receives an alarm activation signal.
  • a system for detecting the presence of living creatures other than fish in bodies of liquid substantially as described above further including system control means.
  • the system control means enables a user to modify the sensitivity of the system.
  • the system control means enables a user to deactivate or mute the alarm means.
  • the system control means enables a user to temporarily deactivate or mute the alarm means.
  • the alarm means when the alarm means is deactivated or muted it will not activate even when it receives an alarm activation signal.
  • the alarm means includes at least one audible alarm.
  • the alarm means includes at least primary and secondary alarm means.
  • the primary alarm means is located near the body of liquid.
  • the secondary alarm means is located remotely from the body of liquid, such as inside the dwelling of the owner of the body of liquid.
  • Figure 1 is a relational flow diagram of the improved preferred embodiment of pool alarm system of the present invention
  • Figure 2 shows a perspective view of a transducer of the preferred embodiment
  • Figure 3 shows a side view of a transducer of the preferred embodiment
  • Figure 4 shows a plan view of a pool fitted with a single transducer, showing the path of acoustic energy beams sent out by the transducer of this embodiment
  • Figure 5 is a side view of the pool of figure 4 showing the shape of the acoustic energy beam transmitted by a single transducer;
  • Figure 6 is a plan view of a swimming pool fitted with two transducers, showing the path of the two acoustic energy beam sets;
  • Figure 7 is a side view of the pool of figure 6 showing the cross-section of the acoustic energy beam shapes
  • Figure 8 is a perspective view of a single acoustic energy beam
  • Figure 9 is a perspective view of a near pool area showing a control panel of the preferred embodiment fitted to a wall and connection line 5 linking the control panel, transducer, power source and alarm;
  • Figure 10 shows a front view of the control panel of the preferred embodiment of the present invention
  • Figure 11 shows a cross-sectional side view of the control panel of the preferred embodiment.
  • the pool alarm system 1 includes a transducer driver 2 which enables a transducer 3 to transmit acoustic energy through a body of liquid 4.
  • the acoustic energy 6 transmitted by the transducer 3 is a supersonic wave.
  • the transducer 3 is not only capable of emitting acoustic energy 6 but is also capable of receiving reflected acoustic energy 7. In this preferred embodiment, such reflected acoustic energy 7 is in the form of a supersonic echo 8.
  • the transducer driver 2 and transducer receiver 9 will communicate with a micro-computer 10 which is linked to a control panel 11, memory bank 12 and an alarm driver 13.
  • the micro-computer 10 interacts with the transducer driver 2 causing the transducer to emit a series of beams 14 of supersonic waves 5.
  • the micro-computer 10 compares the echo 8 with a reference echo 15 stored in the memory bank 12.
  • the reference echo 15 includes at least an empty pool reference echo 16 indicating the type of echo 16 that can be expected when the body of liquid 4, such as a swimming pool 23 is empty.
  • the memory bank 12 also includes a living creature reference echo 17 which represents the type of echo one could expect if a living creature 21 was present within the body of liquid.
  • a living creature reference echo 17 would have a hollow 18 therewithin which generally corresponds to the air inside the living creature 21.
  • a child between the age of 2 to 4 years contains approximately 150 to 200 millilitres of air at rest.
  • the pool alarm system 1 of the preferred embodiment is easily able to detect a supersonic echo 8 having a hollow 18 therewithin of such a size.
  • the pool alarm system 1 of the present invention there would typically be a range of living creature reference echos 17, representing humans, animals and/or bird of various shapes and sizes.
  • living creature reference echos 17 would not only typically have a hollow 18 therewithin but would also be softer returns than the returns received from inanimate objects such as tree branches "Creepy Crawlies", pool chairs and the like, enabling the system to discern between the different signals and to only set off an alarm if a living creature 21 is present in the body of liquid 4.
  • the control panel 11 would interact with the micro computer 10 to perform such functions as adjusting the sensitivity of the alarm, for example, when the system 1 is being initially installed.
  • the control panel 11 of the preferred embodiment would also enable a user to turn the system on or off and to mute the system when people wish to swim in the pool 23.
  • the control panel 11 would be mounted near the entry to the pool area 19.
  • a user When entering the pool area 19 a user would press a swim/mute button 20 on the control panel 12 which would mute the alarm until all activity in the pool 23 had ceased for a certain period of time, for example 15 minutes. After this period of time, the system 1 of the preferred embodiment would automatically re-arm itself and initiate the alarm 22 if it detected the presence of a living creature 21 in the swimming pool 23.
  • the micro-computer 10 and alarm driver 13 interact so that when the micro-computer 10 determines that a reflected echo 8 corresponds to a living creature reference echo 17 stored within the memory bank 12, an alarm activation signal 24 is sent to the alarm driver 13. If the system 1 is on and is not muted, the alarm driver 13 then triggers the alarm 22.
  • the pool alarm system 1 includes at least one acoustic alarm positioned near the body of liquid 4 and a second acoustic alarm located inside the home 25 of the body of liquid 4 owner. It will be appreciated that the present invention has application not only in relation to swimming pools 23, but also to spas, dams and similar bodies of water in which secondary alarms may need to be placed even more remotely from the body of liquid 4.
  • FIG 2 shows a perspective view of a transducer 3 of the preferred embodiment.
  • This transducer 3 is capable of transmitting and receiving acoustic energy 6 such as supersonic waves 5 and is preferably mounted on an internal wall 26 of a swimming pool 23 or other body of liquid 4 by any suitable means.
  • the transducer of the preferred embodiment includes securing holes 27 in the sides thereof through which bolts 28 may pass into the internal wall 26 of the swimming pool 23.
  • Figure 3 shows a side view of a transducer 3 according to a preferred embodiment. Once installed in pool 23 the central panel 29 of the transducer 3 would abut or be flush against the internal wall 26 of the swimming pool 23, with the back portion 30 of the transducer being embedded within the pool wall.
  • a connecting cable 31 links the transducer 23 to the microcomputer 10 within the control panel 11.
  • transducers 3 may be suitable for the purposes of the present invention, including transducers 3 which only transmit acoustic energy 6, thus requiring a separate receiver to receive the reflected acoustic energy 7.
  • the preferred embodiment includes a transducer 3 which is able to perform both transmitting and receiving functions.
  • Figure 4 shows one embodiment of the present invention in which a single transducer 3 is installed in an internal wall 26 of a swimming pool 23.
  • the diagonal lines splaying from the transducer 3 show the series of beams 14 of supersonic waves 5 transmitted through the body of liquid 4 by the transducer 3.
  • Figures 5 and 8 show that these beams 14 are generally conical in shape.
  • the transducer 3 is placed in such a position so as to cover the entire swimming pool 23 with an array of beams 14.
  • FIG. 6 shows a plan view of an alternative embodiment of the pool alarm system 1 of the present invention wherein two transducers 3 are employed at opposite ends of a swimming pool 23.
  • Each transducer 3 transmits an array of beams 14 of supersonic waves 15 and receives the supersonic echos 8 reflected off the internal walls 26 and other objects within the swimming pool 23.
  • the transducers 3 are positioned within the swimming pool 23 such that the beams transmitted therefrom span the entire swimming pool 23 area.
  • the beams 14 omitted from the transducers 3 are aligned such that their upper extremities 32 are parallel with the surface 33 of the body of liquid 4. Due to their conical shape, the lower extremities 34 of the beams 14 are at inclined angles to the surface 33 of the body of liquid 4, so that, as you move away from the transducer 3, the beams 14 pervade an increased depth of the body of liquid 4.
  • the shape of the body of liquid 4 will ultimately determine the number of transducers 3 needed to emit an array of beams 14 sufficient to span the area just below the surface 33 of the entire body of liquid 4. This is so that any foreign objects, such as small children, entering the pool at any point, will be detected.
  • control panel 11 of the preferred embodiment is preferably installed near the entrance 35 to a pool area 19.
  • Figure 9 shows a control panel 11 installed in a wall 36 adjacent to the entrance 35 to a pool area 19.
  • Figure 9 also shows a connecting lead 37 linking the control panel 11 to a source of mains power 38, a connecting lead linking the control panel 11 with an alarm 22 in the home 25 of the pool owner and a further connecting lead 40 linking the control panel 11 to the transducer(s) 3.
  • the control panel 11, alarm 22 and transducer 3 need not necessarily be linked by cords and may be linked by wireless means such as infra-red or radio signals.
  • the control panel 11 of the preferred embodiment preferably has battery back-up means 41 just in case the mains power 38 fails.
  • FIG 10 shows a detailed front view of the control panel 11 of the preferred embodiment.
  • This preferred control panel 11 includes on/off switch 42 which turns the system on and off, swim/mute button 20 which temporarily mutes the alarm to allow people to swim in the pool, sensitivity increasing and decreasing buttons 43 and 44 to increase or decrease the sensitivity of the alarm, a power light 45 to indicate whether the system is on and an alarm light 46 to indicate that the alarm is active.
  • the installer should adjust the sensitivity of the system using sensitivity increasing and decreasing buttons 43 and 44 so that the system will not be tripped by foreign bodies other than living creatures entering the body of liquid 4.
  • Figure 11 shows a sectional side view of the control panel 11 of the preferred embodiment including attachment bolts 47 for connecting the control panel 11 to a wall 36 or other suitable object.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Acoustics & Sound (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
  • Emergency Alarm Devices (AREA)

Abstract

L'invention concerne un système pour détecter la présence d'êtres vivants autres que des poissons dans des masse de liquide. Le système comprend: des émetteurs positionnés dans le liquide permettant la transmission d'énergie acoustique dans la masse de liquide; des récepteurs positionnés dans la masse de liquide pour recevoir l'énergie acoustique réfléchie; dans lesquels au moins une partie de l'énergie acoustique réfléchie reçue par lesdits récepteurs est comparée à au moins une référence d'énergie acoustique réfléchie et un signal d'activation d'alarme est créé si au moins une partie de ladite énergie acoustique réfléchie correspond au moins partiellement à une référence d'énergie acoustique réfléchie d'êtres vivants. La référence d'énergie acoustique réfléchie par l'être vivant est de préférence l'énergie acoustique réfléchie pouvant être reçue par lesdits récepteurs lorsqu'un être vivant se trouve dans ladite masse de liquide. De préférence, la référence d'énergie acoustique réfléchie par l'être vivant est caractérisée par une région centrale ayant une énergie acoustique faible ou inexistante, qui correspond à l'air contenu dans l'être vivant. De préférence, l'énergie acoustique comprend une onde acoustique et idéalement au moins une onde acoustique supersonique.
PCT/AU2000/000262 1999-03-29 2000-03-29 Systeme d'alarme ameliore pour piscine WO2000058753A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU34089/00A AU3408900A (en) 1999-03-29 2000-03-29 Improved pool alarm system

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AUPP9481A AUPP948199A0 (en) 1999-03-29 1999-03-29 Improved pool alarm system
AUPP9481 1999-03-29

Publications (1)

Publication Number Publication Date
WO2000058753A1 true WO2000058753A1 (fr) 2000-10-05

Family

ID=3813677

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/AU2000/000262 WO2000058753A1 (fr) 1999-03-29 2000-03-29 Systeme d'alarme ameliore pour piscine

Country Status (2)

Country Link
AU (1) AUPP948199A0 (fr)
WO (1) WO2000058753A1 (fr)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1624427A1 (fr) * 2004-08-05 2006-02-08 Vincent Robert Brewer Alarme pour piscine
WO2006087124A1 (fr) * 2005-02-17 2006-08-24 Atlas Elektronik Gmbh Dispositif de surveillance pour canal d'amenee d'eau
WO2007060378A1 (fr) * 2005-11-23 2007-05-31 Osl Group Holdings Limited Alarme de piscine
EP2466562A1 (fr) * 2010-12-16 2012-06-20 Tamarit López, Ana Magdalena Système d'alarme pour les piscines
ITBS20120133A1 (it) * 2012-08-31 2014-03-01 Greci Cristian Sistema anti intrusione della piscina
FR3001566A1 (fr) * 2013-01-31 2014-08-01 Datasharing Dispositif et procede de detection d'un corps vivant
US9978245B2 (en) 2015-03-17 2018-05-22 Safepool Technologies, Llc Systems for sensing pool occupants and regulating pool functions

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4747085A (en) * 1984-05-01 1988-05-24 Gerald W. Dunegan Method and apparatus for monitoring swimming pools
US5043705A (en) * 1989-11-13 1991-08-27 Elkana Rooz Method and system for detecting a motionless body in a pool
US5195060A (en) * 1991-12-10 1993-03-16 Marcorp Inc. Security system for swimming pools and like bodies of water
WO1995012135A1 (fr) * 1993-10-29 1995-05-04 Splash Industries, Inc. Alarme pour piscine

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4747085A (en) * 1984-05-01 1988-05-24 Gerald W. Dunegan Method and apparatus for monitoring swimming pools
US5043705A (en) * 1989-11-13 1991-08-27 Elkana Rooz Method and system for detecting a motionless body in a pool
US5195060A (en) * 1991-12-10 1993-03-16 Marcorp Inc. Security system for swimming pools and like bodies of water
WO1995012135A1 (fr) * 1993-10-29 1995-05-04 Splash Industries, Inc. Alarme pour piscine

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1624427A1 (fr) * 2004-08-05 2006-02-08 Vincent Robert Brewer Alarme pour piscine
WO2006087124A1 (fr) * 2005-02-17 2006-08-24 Atlas Elektronik Gmbh Dispositif de surveillance pour canal d'amenee d'eau
DE102005007207A1 (de) * 2005-02-17 2006-08-24 Atlas Elektronik Gmbh Überwachungseinrichtung für einen wasserführenden Zulaufkanal
DE102005007207B4 (de) * 2005-02-17 2008-04-24 Atlas Elektronik Gmbh Überwachungseinrichtung für einen wasserführenden Zulaufkanal
WO2007060378A1 (fr) * 2005-11-23 2007-05-31 Osl Group Holdings Limited Alarme de piscine
EP2466562A1 (fr) * 2010-12-16 2012-06-20 Tamarit López, Ana Magdalena Système d'alarme pour les piscines
ITBS20120133A1 (it) * 2012-08-31 2014-03-01 Greci Cristian Sistema anti intrusione della piscina
FR3001566A1 (fr) * 2013-01-31 2014-08-01 Datasharing Dispositif et procede de detection d'un corps vivant
US9978245B2 (en) 2015-03-17 2018-05-22 Safepool Technologies, Llc Systems for sensing pool occupants and regulating pool functions

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