AU596027B2

AU596027B2 - Swimming pool warning device

Info

Publication number: AU596027B2
Application number: AU21727/88A
Authority: AU
Inventors: Anthony John Webb
Original assignee: DOMINIC STILLITANO
Current assignee: Stillitano Dominic
Priority date: 1987-08-31
Filing date: 1988-08-31
Publication date: 1990-04-12
Anticipated expiration: 2008-08-31
Also published as: AU2172788A

Description

ii\ 4: F i, 1 d .i a 1 i COMMONWEALTH OF AUSTRALIA Patents Act 1952 COMPLETE SPECIFICATION5 9 2 (Original) FFE FOR OFFICE USE Application Number: PI4082 Class Lodged: 31 August, 1987 Complete Specification Lodged: Accepted: Publishe: Int. Class Priority: Related Art: Tz TO BE COMPLETED BY APPLICANT Name of Applicant: DOMINLtJ SSLLVTA00 DF.rF-P-N(M-I-NEE-S-P-TF-Y--;---L Address of Applicant: 5'2> 2ue~S(^ay (P5& f.A(SDi?!^ -Let--3--A-l-e-ande-r-r-i-ve-Mal-aga-, in the State of Western Australia, Commonwealth of Australia.

Actual Inventor: ANTHONY JOHN WEBB P000526 31 /08/88 Address for Service:- Wray Associates Primary Industry House 239 Adelaide Terrace Perth Western Australia 6000.

Complete Specification for the invention entitled: "Swimming Pool Warning Device" The following statement is a full description of this invention, including the best method of performing it known to me:- 1

'Y.

-i r E. 1 THE COMMISSIONFR OF PAT ENIS Ihis form must be accompamnied by elthef a v, oi Ssi', 'in OI r 9 and ltue (;opl iya comp1l e t lspe'.ilcatlion (Forim 10 and tru copy) -2- THIS INVENTION relates to a warning device for generating a warning signal upon unauthorised entry into a body of water.

The invention has been devised particularly, although not solely, as a warning device for use with a swimming pool to provide a warning in the event of unauthorised entry into a swimming pool such as when a small child or other person who does not have competent swimming abilities, falls or otherwise enters the swimming pool.

There have been numerous proposals concerning warning devices which are adapted to generate a warning signal when a person (particularly a child) falls or otherwise enters a swimming pool without supervision. Many proposed warning devices are in the form of proximity detectors which respond to a person entering a prescribed area surrounding the swimming pool. Such proximity devices have Snot proved altogether satisfactory owing to the fact that they are actuated when a person enters the prescribed area notwithstanding that the person may subsequently leave the area without entering the swimming pool. Other proposed warning devices are arranged to detect disturbances in water in a swimming pool arising from a person entering 0 the water. A deficiency of warning devices which detect water disturbances is that such devices are susceptible to erroneous operation when water disturbances are generated by other influences such as strong winds or objects being thrown into the water. If the sensitivity of the detecting device is reduced so as not to respond to such influences, n there is some likelihood that the detector may be ineffectual as it may not necessarily respond to water disturbances arising from a very small child entering the water.

~P I ih -3- The present invention seeks to overcome the above mentioned deficiencies of existing warning devices by providing a warning device which is responsive to a disturbance in a body of water but only after a person has been detected in the vj.cinity of the body of water.

Accordingly, the invention in one form resides in a warning device comprising a first means for detecting the presence of a person in the vicinity of a body of water, a, o and a second means for detecting disturbances in the body 10 of water and for providing a, warning signal in response o'o ,thereto but only after said first means has detected the presence of a person in the vicinity of the body of water.

1o a i With this arrangement, said second means will not produce a warning signal if the water is disturbed by some other oo", influence (such as strong winds) which have not first been St detected by the first detecting means.

The first detecting means may be of any suitable form such as a microwave movement detector, a passive infrared detector, a photoelectric beam, a magnetic read switch, a low pressure air switch.

*a It The second detecting means may comprise a device for detecting wave motion in the body of water. The device may comprise an electrical circuit including two probes which are so arranged that the circuit between the probes is completed when both probes are simultaneously in contact with water as a result of wave motion in the body of water. Preferably, one probe is arranged so as to be continuously immersed in the body ot water and the other is positioned so as to be spaced above the water level when there is no significant wave motion in the body of water. The second probe is suitably spaced above the water level such that it is contacted by waves produced within a -4the body of water when there is significant wave motion within the water (such as that wave motion generated when a person falls into the body of water) Preferably, the two probes are mounted on a support which permits positional adjustment of the two probes so as to accommodate changes in the water level within the body of water.

*1 I The invention will be better understood by reference to the following description of one specific embodiment thereof as shown in the accompanying drawings in which:- Figure 1 is a block diagram of a warning device according to the embodiment; Figure 2 is a schematic view of part of a second detecting means for detecting water disturbances in f a body of water; and Figure 3 is a schematic view of a track for adjustably supporting the part illustrated in Figure 2.

The embodiment shown in the drawings is directed to a 420 warning device for detecting unauthorised entry of persons into a swimming pool.

The detecting device comprises a first detecting means for detecting the presence of a person in the vicinity of the swimming pool. The swimming pool may, for example, be bounded by a fence provided with an accessway through

'K

which a person may enter to gain access to the swimming pool and the first detecting means may be arranged to detect movement of a person through that accessway. In this embodiment, the first detecting means is in the form of a photoelectric beam, but it may be of any other construction such as a microwave movement detector, a 0 .L p2 ill/ ICII*I-I)LI^. ilil ~IICle-~~ -i~il Iniii-l-ii-l--- iii XilLL~---L-II~_--__il passive infra red detector, magnetic read switch, or low pressure air switch.

The first detecting means is arranged to generate a signal in response to the presence of a person An the vicinity of the swimming pool, the signal being applied to an electrical circuit illustrated in block diagram form in Figure 1 of the drawings, operation of which will be described later.

o 4 04 t The swimming pool warning device further comprises a 0 second detecting means for detecting disturbances in the 4' body of water. The second detecting means 1i includes a pair of electrical probes 12 and 13. The two probes comprise a first probe 1.2 which is positioned so as to be continuously immersed within water in the swimming pool and a second probe 13 (being a detection probe) which is 4 shorter than the first probe and which is positioned above the normal water level within the pool when there are no significant disturbances within the pool. The spacing of Ii the second probe 13 above the water level is, however, arranged so that the probe will be contacted by waves generated in the body of water when the water is disturbed q as a result of a person falling into the swimming pool.

a t When both probes are immersed in the water, an electrical conductivity path is provided between the probes by the water.

A third probe 14 is also provided and the three probes are mounted on a body 15 which is adjustably positioned in a track 16 (as shown in Figure 3) so that the position of the probes relative to the water level can be selectively varied according to changes in the water level. The third probe 14 is longer than the second probe 13 while being shorter than the first probe 12. The probe 14 is intended to be immersed in the pool water and co-operates with the -6first probe 12 in an electrical circuit which is arranged to actuate the alarm in the event of the water level falls to such an extent that the probe 14 is no longer in contact with the water. This is a safety measure as it provides the pool owner with an indication of the drop in water level before the level drops so much that the first probe is no longer in contact with the water. If the water level were to drop to such an extent that probe 1 was out of contact with the pool water, the warning device would be inoperative.

0a The warning device also incorporates an alarm including buzzer 37 or other alarm device which is actuated when the otto o water level rises about a predetermined maximum level.

ct The maximum water level is determined by the relative position of the second probe 13 and the buzzer 37 is actuated when the three probes are immersed in water.

q t Operation of the warning device will now be described. The 'track 16 with body 15 located therein, is mounted on a 4 4i wall of the swimming pool with the first and third probes located below the water level and the second probe 13 located above the water level. When a child or other person passes through the accessway into the prescribed vicinity of the swimming pool, the first detecting means detects the presence of such person and produces an electrical signal in response thereto.

The signal so produced is applied to first flip-flop 19 which toggles and goes low to initiate second flip-flop 23. Toggling of first flip-flop 19 also operates a switch which initiates operation of timer 27. The time runs for a predetermined period of time, for instance two minutes. If there is no disturbance created in the pool water within said period of time, a reset pulse is sent to the two ~1 7 It, 4 4r 4 4, 4 4 44 flip-flops 19 and 23. If, on the other hand, a person does enter the pool generated within the specified time, wave motion generated within the water creates an electrical path between the first and second probes 12 and 13 respectively. The electrical signal generated by creation of the electrical path between the two probes causes operation of the second flip-flop 23 which goes low thereby initiating three events. First, relay 29 is turned on so as to stop the reset pulse for the flip-flops.

Secondly, a visual alarm device (such as a strobe light) is activated, thirdly, a timer 31 is activated. The timer 31 turns on switch 33 so as to activate an audible alarm 35 for the period determined by the timer. At the end of that period of time, the switch 33 is turned off so as to terminate the audible alarm. However, the visual alarm remains operative until such time as the system is reset by the pool owner. This feature ensures the warning device has operated even though the owner may not have been present to hear the audible alarm.

44 &r ;i r -;r r7X~g~p~ I

Claims

11. A warning device comprising a first means for detecting the presence of a person in the vicinity of a body of water, and a second means for detecting disturbances in the body of water and for providing a warning signal in response thereto but only after said first means has detected the presence of a person in the vicinity of the body of water. 0 t~ 2. A warning device according to claim 1 wherein the first detecting means is selected from a group comprising a microwave movement detector, a passive infrared 4 detector, a photoelectric beam, a magnetic read switch and a low pressure air switch. 3. A warning device according to claim 1 or 2 wherein the second detecting means comprises a device for detecting wave motion in the body of water. *I t 4. A warning device according to claim 3 wherein said device for detecting motion comprises an electrical circuit including two probes arranged such that the circuit between the probes is completed when both probes are simultaneously in contact with water as a result of wave motion in the body of water. A warning device according to claim 4 wherein one of said prcbes is intended in use to be continuously immersed in the body of water and the other is intended in use to be spaced above the water level when there is no significant wave motion in the body of water. 6. A warning device according to claim 4 or 5 wherein the two probes are mounted on a support which permits positional adjustment of the two probes so as to -i 9 accommodate changes in the water level within the body of water. 7. A warning device according to any one of the preceding claims further comprising means to provide an alarm signal in the event of the level of the body of water falling below a prescribed minimum level. 8. A warning device according to claim 7 wherein said means includes a third probe having a length intermediate the lengths of said two probes. 9. A warning device according to any one of the preceding claims wherein the device further comprises means to provide an alarm signal in the event of the water level rising above a prescribed maximum level. A warning device substantially as herein described with reference to the accompanying drawings. 0, 01 P C DATED this thirty-first day of t I August, 1988. NOM-I-NEES -PTY. -LTD. Applicant. WRAY ASSOCIATES, Perth, Western Australia, Patent Attorneys for the Applicant. .hiiiL~ i t..