Patent Publication Number: US-10311699-B2

Title: Swimming pool entrance detector

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. National Phase Application under 35 U.S.C. 371 of International Application No. PCT/IL2017/050411, which has an international filing date of Apr. 4, 2017, and which claims priority and benefit from Israel Patent Application No. 245341, filed Apr. 21, 2016, the contents and disclosure of which are incorporated herein by reference in their entirety. 
     TECHNICAL FIELD 
     The invention relates to the field of swimming pools safety. More particularly, the invention relates to a detector for indicating an entering to the swimming pool. 
     BACKGROUND 
       FIG. 1  depicts a swimming pool, and the problem concerned. 
     A swimming pool  12 , while not being used, must be covered by a cover  18 , for protecting of the accidental entrance of children and the like while the swimming pool is not guarded, and prevention of accidental drowning. 
     However, children might enter by creating an opening of the pool cover  14   a  that allows entering the pool. 
     The conventional solution to the problem is by video means or by motion sensor. However, without super quality and expensive means, these solutions provide false alarms, as they can alert also in other irrelevant cases and not just focused to the case to be indicated. 
     US20130313204 discloses light sensors to determine whether an spa is covered or not. 
     However, US20130313204 does not provide a solution for alerting upon presence of one of various local/partial openings  14   a  of pool cover  18 . 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts a swimming pool, requiring indication of an undesired opening of the cover. 
         FIG. 2  depicts the swimming pool of  FIG. 1 , including a swimming-pool entrance detector according to one embodiment of the invention. 
         FIG. 3  depicts the swimming-pool entrance detector of  FIG. 2  disassembled. 
         FIG. 4  depicts the swimming-pool entrance detector of  FIG. 2  floating in the water of the swimming pool of  FIG. 2 . 
         FIG. 5  is a front sectional view of a swimming pool having an opening in the cover and the swimming-pool entrance detector of  FIG. 2 . 
         FIG. 6  is an electronic circuit, for showing the principle of the analysis of the electronic unit of  FIG. 3 . 
         FIG. 7  is a front sectional view of a swimming pool having the swimming-pool entrance detector of  FIG. 2 , but not having the opening of the swimming pool cover. 
         FIG. 8  is a front sectional view of the swimming pool of  FIG. 7 , in which the cover is partially transparent. 
         FIG. 9  is a front sectional view of the swimming pool having two openings and the swimming-pool entrance detector of  FIG. 2 . 
         FIG. 10  is a front sectional view of the swimming pool being entirely exposed, and having the swimming-pool entrance detector of  FIG. 2 . 
         FIG. 11  is a front sectional view of the swimming pool having one of the openings, and the swimming-pool entrance detector of  FIG. 2  facing that opening. 
         FIG. 12  is an electronic circuit, for showing the principle of the analysis of the electronic unit for the case of  FIG. 11 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 2  depicts the swimming pool of  FIG. 1 , including a swimming-pool entrance detector according to one embodiment of the invention. 
     One or more swimming-pool entrance detectors  10   a  according to the invention may warn upon the creation of opening  14   a.    
     Swimming-pool entrance detector  10   a  preferably floats on the water or may be submersed in the water. Unlike depicted in the figure, it is not necessary that swimming-pool entrance detector  10   a  be located against opening  14   a . Swimming-pool entrance detector  10   a  may also be integrated in the pool structure, for example, the electronic parts of the detector may be integrated, mounted, or attached to the walls of the pool, or to the pool cover. 
       FIG. 3  depicts the swimming-pool entrance detector of  FIG. 2  disassembled. 
     Swimming-pool entrance detector  10   a  can include a sealed compartment  50  for containing air, sufficient for creating some buoyancy. Further to the optical sensing of the cover position, an accelerometer  44  may utilize the floating, for detecting sudden movement, indicating motion of a person disposed within the swimming pool. 
     Compartment  50  includes casing members  20   a  and  20   b ; a top lens  22 , for facing the sky or cover  18  of  FIG. 2 ; and a bottom lens  24 , for facing the ground of swimming pool  12  of  FIG. 2 . 
     Compartment  50  contains a top optical sensor  28 , for receiving illumination through top lens  22 ; a bottom optical sensor  30 , for receiving illumination through bottom lens  24 ; an electronic unit  26 , which may include an alarm unit  54 , such as a wireless transmitter; and batteries  32 , for powering electronic unit  26 . 
       FIG. 4  depicts the swimming-pool entrance detector of  FIG. 2  floating in the water of the swimming pool of  FIG. 2 . 
     Another function of batteries  32  is for providing weight to swimming-pool entrance detector  10   a , for lowering the top thereof, such that top lens  22  is disposed underwater near the water level  52 . Compartment  50  is shaped and batteries  32  are housed therewithin, such that lens  22  maintains the top position and lens  24  maintains the bottom position. 
       FIG. 5  is a front sectional view of the swimming pool having the opening and the swimming-pool entrance detector of  FIG. 2 . 
     Swimming-pool entrance detector  10   a  is disposed above the ground  56 , and top optical sensor  28  thereof faces the top  58 . Even though opening  14   a  is disposed at the right side of swimming pool  12  and swimming-pool entrance detector  10   a  is disposed at the left side thereof, a ray  40   a   1 , such as from the sun  60  being at the top  58 , enters opening  14   a , is reflected to ray  40   a   2 , and may disperse towards bottom optical sensor  30 . In contrast to bottom optical sensor  30 , in this case, ray  40   a   1  does not reach top optical sensor  28 , due to cover  18 . 
       FIG. 6  is an electronic circuit, for showing the principle of the analysis of the electronic unit of  FIG. 3 . 
     Electronic unit  26 , which may constitute a comparator for detecting a significant difference between the intensity on top optical sensor  28  and bottom optical sensor  30 , analyses presence of opening  14   a , and thus turns on alarm unit  54 . 
     Electronic unit  26  may further include a memory, for detecting differences along time, for the same sensor, such as described following. 
     During creating opening  14   a , electronic unit  26  detects a positive intensity gradient on bottom optical sensor  30  and a non-significant intensity gradient on top optical sensor  28 . According to this, electronic unit  26  identifies the creation of opening  14   a.    
       FIG. 7  is a front sectional view of the swimming pool not having the opening and the swimming-pool entrance detector of  FIG. 2 . 
     In case that opening  14   a  is not present, ray  40   a   1  neither reaches top optical sensor  28 , nor bottom optical sensor  30 , due to cover  18 . 
     Electronic unit  26  (shown in  FIG. 3 ) detecting equal intensity on top optical sensor  28  and on bottom optical sensor  30 , analyses absence of opening  14   a , and thus turns off alarm unit  54 . 
       FIG. 8  is a front sectional view of the swimming pool of  FIG. 7 , in which the cover is partially transparent. 
     Even if cover  18  partially transfers ray  40   a   1 , due to absorbing a portion thereof, electronic unit  26  (shown in  FIG. 3 ) will still detect that the intensity of ray  38   a , being the remainder of the absorbance, reaching top optical sensor  28 , is substantially equal to the intensity of the reflected ray  38   b  reaching bottom optical sensor  30 , and thus analyses absence of opening  14   a , and thus turns off alarm unit  54 . 
     In another aspect, in this case, once the sun gets out of a cloud, electronic unit  26  detects equal difference both to top optical sensor  28  and to bottom optical sensor  30  and concludes absence of opening  14   a.    
       FIG. 9  is a front sectional view of the swimming pool having two openings and the swimming-pool entrance detector of  FIG. 2 . 
     Even though openings  14   a  and  14   b  are disposed at the right and left sides of swimming pool  12  and swimming-pool entrance detector  10   a  is disposed at the center thereof, rays  40   a   1  and  40   b   1  enter openings  14   a  and  14   b  respectively, are reflected to rays  40   a   2  and  40   b   2  respectively, and may disperse towards bottom optical sensor  30 . In contrast to bottom optical sensor  30 , in this case, rays  40   a   1  and  40   b   1  do not reach top optical sensor  28 , due to cover  18 . 
     Electronic unit  26  (shown in  FIG. 3 ) detecting a significant difference between the intensity on top optical sensor  28  and bottom optical sensor  30 , analyses presence of openings  14   a  and  14   b , and thus turns on alarm unit  54 . 
       FIG. 10  is a front sectional view of the swimming pool being entirely exposed, and having the swimming-pool entrance detector of  FIG. 2 . 
     Upon removing cover  18 , rays  40   a   1  and  40   b   1  enter, are reflected and may disperse towards bottom optical sensor  30 . In this case, rays  40   a   1  and  40   b   1  as well reach top optical sensor  28 . 
     Electronic unit  26  (shown in  FIG. 3 ) detecting no significant difference between the intensity on top optical sensor  28  and bottom optical sensor  30 , analyses absence of openings  14   a  and  14   b , and thus turns off alarm unit  54 . 
       FIG. 11  is a front sectional view of the swimming pool having one of the openings, and the swimming-pool entrance detector of  FIG. 2  facing that opening. 
     In this example opening  14   b  is disposed at the left side of swimming pool  12 , and swimming-pool entrance detector  10   a  as well is disposed at the left. Ray  40   b   1  enters openings  14   a , is reflected and may disperse towards bottom optical sensor  30 . However, ray  40   a   1  cannot enter opening  14   b  for being reflected towards bottom optical sensor  30 . 
     In contrast to bottom optical sensor  30 , in this case, both of rays  40   a   1  and  40   b   1  reach top optical sensor  28 , through opening  14   b.    
     Electronic unit  26  (shown in  FIG. 3 ) detects the difference between the intensity on top optical sensor  28  and bottom optical sensor  30 , analyses presence of opening  14   b , and thus turns on alarm unit  54 . 
       FIG. 12  is an electronic circuit, for showing the principle of the analysis of the electronic unit for the case of  FIG. 11 . 
     The reading of top optical sensor  28  may be stored in a memory  36 A, for comparing by a comparator  42 A, this reading with the current reading of top optical sensor  28 . The reading of bottom optical sensor  30  may be stored in a memory  36 B, for comparing by a comparator  42 B, this reading with the current reading of top optical sensor  28 . 
     Thus, in another aspect, during creating opening  14   b , electronic unit  26  detects by a comparator  42 C, comparing the outputs of comparators  42 A and  42 B, that the positive intensity gradient on top optical sensor  28  is greater than the positive intensity gradient on bottom optical sensor  30 . According to this, electronic unit  26  identifies the creation of opening  14   b.    
     Referring again to  FIG. 11 , for a large swimming pool, it is preferable to provide swimming-pool entrance detector  10   a  to an additional swimming-pool entrance detector  10   b , which will not receive ray  40   b   1 .
         Numerals  10   a  and  10   b  denote swimming-pool entrance detectors according to one embodiment of the invention;   numeral  12  denotes a swimming pool;   numeral  14   a  and  14   b  denote undesired opening in the cover; swimming-pool entrance detectors  10   a  and  10   b  are intended for warning presence of the opening;   numeral  18  denotes a cover of the swimming pool, for not allowing children and the such to enter the swimming pool;   numerals  22  and  24  denote lenses;   numerals  20   a  and  20   b  denote two members of the packaging/casing of the swimming-pool entrance detector, which function together also as a float, since they house air in a sealed manner;   numeral  26  denotes the electronic unit; the main element thereof is a comparator, which may be electronic or a controller, for comparing the signal of the top optical sensor  28  with the signal of the bottom optical sensor  30 ;   numeral  28  denotes the optical sensor disposed at the top;   numeral  30  denotes the optical sensor disposed at the bottom;   numerals  32  denotes a battery for powering the swimming-pool entrance detector;   numeral  34  denotes a subsidiary compartment for housing one or more batteries;   numerals  36 A and  36 B denote memory units of the electronic unit;   numeral  38   a  denotes a rays being decreased due to absorbance of the cover  18 ;   numeral  38   b  denotes a ray being reflected or dispersed;   numerals  40   a   1  and  40   b   1  denote rays from the sun or another illumination source propagating from the top of the swimming pool;   numeral  40   a   2  and  40   b   2  denote rays reflected/dispersed from rays  40   a  and  40   b   1  respectively;   numeral  42  denotes a comparator of the electronic unit;   numeral  44  denotes an accelerometer, for detecting a person falling into the swimming pool;   numeral  50  denotes a compartment packaging/casing the swimming-pool entrance detector, which functions also as a float, since it houses air in a sealed manner;   numeral  52  denotes the water level;   numeral  54  denotes an alarm unit, which may include a loudspeaker and/or a transmitter and/or a visual indicator and/or a receiver, for being controlled by remote;   numeral  56  denotes the ground of the swimming pool;   numeral  58  denotes the space above the swimming pool, such as the sky or the sun or an artificial illumination source illuminating from above the swimming pool; and   numeral  60  denotes the sun, providing beams/rays, which they and/or reflected rays therefrom are sensed by the swimming-pool entrance detector.