Patent Publication Number: US-2021172823-A1

Title: Self-powered water leakage detector

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a self-powered water leakage detector. 
     Description of the Related Art 
     Various water leakage detectors are manufactured for detecting water leakage in apparatuses and workshops where liquids such as water are used (see, for example, Japanese Patent No. 4218020). A band-shaped water leakage detector that has been used heretofore operates by supplying electric power to two electrically conductive bands, detecting a short circuit made between the electrically conductive bands by a water leakage to thereby determine the water leakage, and transmitting a signal reporting on the water leakage. 
     SUMMARY OF THE INVENTION 
     The band-shaped water leakage detector referred to above needs to supply the electrically conductive bands with electric power at all times and also requires electric power for generating reporting signals. Therefore, the power supply of the band-shaped water leakage detector tends to limit sites where the band-shaped water leakage detector can be installed. In a case where a battery is used as the power supply, the band-shaped water leakage detector may possibly be unable to detect a water leakage in case of need due to a deterioration of the battery. Consequently, the existing water leakage detector runs the risk of failing to detect a water leakage. 
     It is therefore an object of the present invention to provide a self-powered water leakage detector that restrains itself from becoming unable to detect a water leakage. 
     In accordance with an aspect of the present invention, there is provided a self-powered water leakage detector including a water cell having a positive electrode and a negative electrode and a transmitter for transmitting a reporting signal by using electric power generated by the water cell that is brought into contact with water that has leaked. 
     Preferably, the water cell and the transmitter are fixedly housed in a case, and the case is adapted to be placed in an installation site where a water leakage is to be detected. Preferably, when the case is placed in the installation site, the positive electrode and the negative electrode have respective lower ends disposed in a position that is equal to or lower than a level of the water leakage to be detected. 
     Preferably, the reporting signal transmitted by the transmitter is established uniquely to the transmitter. Preferably, the self-powered water leakage detector further includes a light emitting diode (LED) to be turned on using the electric power generated by the water cell. 
     Preferably, the self-powered water leakage detector further includes a water leakage detecting band having a pair of electrically conductive wires insulated from each other, and a sensor for detecting a short circuit caused between the electrically conductive wires by a water leakage. The transmitter transmits the reporting signal indicating the water leakage when the short circuit caused between the electrically conductive wires is detected by the sensor. 
     The self-powered water leakage detector according to present invention is advantageous in that it restrains itself from becoming unable to detect a water leakage. 
     The above and other objects, features and advantages of the present invention and the manner of realizing them will become more apparent, and the invention itself will best be understood from a study of the following description and appended claims with reference to the attached drawings showing some preferred embodiments of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view illustrating a configuration example of a self-powered water leakage detector according to a first embodiment of the present invention; 
         FIG. 2  is a plan view of the self-powered water leakage detector illustrated in  FIG. 1 ; 
         FIG. 3  is a block diagram illustrating a configuration of the self-powered water leakage detector illustrated in  FIG. 1 ; 
         FIG. 4  is a side elevational view of the self-powered water leakage detector illustrated in  FIG. 1 ; 
         FIG. 5  is a diagram illustrating an example of a reporting signal transmitted from a transmitter of the self-powered water leakage detector illustrated in  FIG. 1 ; 
         FIG. 6  is a perspective view illustrating a configuration example of a self-powered water leakage detector according to a second embodiment of the present invention; 
         FIG. 7  is a block diagram illustrating a configuration of the self-powered water leakage detector illustrated in  FIG. 6 ; 
         FIG. 8  is a side elevational view of the self-powered water leakage detector illustrated in  FIG. 6 ; 
         FIG. 9  is a plan view illustrating a configuration example of a self-powered water leakage detector according to a third embodiment of the present invention; 
         FIG. 10  is a block diagram illustrating a configuration of the self-powered water leakage detector illustrated in  FIG. 9 ; and 
         FIG. 11  is a side elevational view of the self-powered water leakage detector illustrated in  FIG. 9 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Preferred embodiments of the present invention will hereinafter be described in detail with reference to the drawings. The present invention is not limited to the details of the embodiments described below. The components described below cover those which could easily be envisaged by those skilled in the art and those which are essentially identical to those described above. Further, the arrangements described below can be used in appropriate combinations. Various omissions, replacements, or changes of the arrangements may be made without departing from the scope of the present invention. 
     First Embodiment 
     A self-powered water leakage detector according to a first embodiment of the present invention will hereinafter be described with reference to  FIGS. 1 through 5 .  FIG. 1  illustrates in perspective a configuration example of the self-powered water leakage detector according to the first embodiment.  FIG. 2  illustrates in plan the self-powered water leakage detector illustrated in  FIG. 1 .  FIG. 3  illustrates in block form a configuration of the self-powered water leakage detector illustrated in  FIG. 1 .  FIG. 4  illustrates in side elevation the self-powered water leakage detector illustrated in  FIG. 1 .  FIG. 5  illustrates an example of a reporting signal transmitted from a transmitter of the self-powered water leakage detector illustrated in  FIG. 1 . 
     A self-powered water leakage detector (hereinafter simply referred to as “water leakage detector”), denoted by  1  in  FIG. 1 , according to the first embodiment is installed at a given installation site  100  in a building for detecting a water leakage at the installation site  100  by detecting whether or not water is present at the installation site  100 . The installation site  100  refers to a site where it is not desirable for water to collect in any of various buildings, i.e., where a water leakage is to be detected. The water leakage detector  1  is installed on a floor  101  of the installation site  100 , for example. 
     As illustrated in  FIGS. 1 and 2 , the water leakage detector  1  includes a case  10 , a water cell  20 , and a transmitter  30 . The case  10 , which provides an outer shell of the water leakage detector  1 , is of a disk shape according to the present embodiment. According to the present invention, however, the case  10  is not limited to a disk shape. The case  10  has a circular bottom surface  11  placed on the floor  101  of the installation site  100 . 
     As illustrated in  FIGS. 1 through 4 , the water cell or water battery  20  has a positive electrode  21  and a negative electrode  22  that are disposed on an outer surface of the case  10  and spaced apart from each other. The positive electrode  21  and the negative electrode  22  are secured to the outer surface of the case  10 . The water cell  20  operates as follows: When the positive electrode  21  and the negative electrode  22  contact water  110  (see  FIG. 4 ) that has leaked into the installation site  100 , they dissolve ions into the water  110  and the dissolved ions move between the positive electrode  21  and the negative electrode  22 , generating electromotive forces between the positive electrode  21  and the negative electrode  22 , i.e., generating electric power. When electromotive forces are generated between the positive electrode  21  and the negative electrode  22 , the water cell  20  generates electric power, thereby detecting the water  110  that has leaked into the installation site  100 . Both the positive electrode  21  and the negative electrode  22  are electrically connected to the transmitter  30  and output the generated electric power to the transmitter  30 . 
     When the case  10  is placed on the floor  101  of the installation site  100 , the positive electrode  21  and the negative electrode  22  have respective lower ends positioned at such a height from the bottom surface  11  of the case  10  that is equal to or lower than a level of the water  110  to be detected that has leaked into the installation site  100 . According to the first embodiment, the respective lower ends of the positive electrode  21  and the negative electrodes  22  are positioned at the same height as the bottom surface  11  of the case  10 . According to the present invention, however, the respective lower ends of the positive electrode  21  and the negative electrodes  22  are not limited to the height illustrated in  FIG. 4 . 
     The transmitter  30  transmits a reporting signal  200  representing information to be reported as illustrated in  FIG. 5 , by using the electric power generated by the water cell  20  when it contacts the water  110  that has leaked into the installation site  100 . According to the first embodiment, the transmitter  30  is housed in the case  10  and fixed to the case  10 . According to the first embodiment, when the transmitter  30  is supplied with electric power from the water cell  20 , the transmitter  30  repeatedly transmits the reporting signal  200  illustrated in  FIG. 5 , by using the electric power generated by the water cell  20  as a power supply. According to the first embodiment, the reporting signal  200  is established uniquely to the transmitter  30 , i.e., the water leakage detector  1 . In other words, different transmitters  30 , i.e., different water leakage detectors  1 , transmit different reporting signals  200 . According to the first embodiment, the reporting signal  200  is a signal used also to distinguish the water leakage detector  1  from other water leakage detectors  1 . According to the present invention, however, the reporting signal  200  is not limited to such use. 
     The transmitter  30  includes a sender for sending a reporting signal  200  when the water cell  20  generates electric power and supplies the electric power to the sender, and a controller for controlling the sender. When the controller establishes a reporting signal  200  and the water cell  20  supplies electric power to the sender, the sender repeatedly sends the established reporting signal  200 , by using the electric power from the water cell  20  as a power supply. The controller controls operation of the sender. According to the first embodiment, the controller is constructed as a dedicated processing circuit, i.e., a piece of hardware, such as a single circuit, a composite circuit, a programmed processor, or parallel-programmed processors. 
     According to the first embodiment, the reporting signal  200  transmitted from the transmitter  30  is received by a terminal apparatus  60  illustrated in  FIGS. 2, 3, and 4 , for example. The terminal apparatus  60  may be a mobile terminal that can be carried by the user thereof, for example. According to the first embodiment, as illustrated in  FIGS. 2 and 3 , the terminal apparatus  60  is in the form of a tablet or a portable computer including a casing  61 , a display unit  62 , an input unit, a wireless communication unit, an arithmetic processing unit having a microprocessor such as a central processing unit (CPU), a storage unit having a memory such as a read only memory (ROM) or a random access memory (RAM), and an input/output interface unit. According to the present invention, however, the terminal apparatus  60  is not limited to a tablet or a portable computer, but may be any of electronic equipment insofar as it can be carried by the user. 
     The casing  61  houses therein at least the wireless communication unit, the arithmetic processing unit, the storage unit, and the input/output interface unit of the terminal apparatus  60 . The arithmetic processing unit of the terminal apparatus  60  performs arithmetic processing operations according to computer programs stored in the storage unit and outputs a control signal for controlling the terminal apparatus  60  via the input/output interface unit to the units of the terminal apparatus  60 . 
     The display unit  62  includes a liquid crystal display unit or the like. The display unit  62  displays characters, still images, moving images, symbols, and figures. 
     The input unit receives operation inputs from the user. According to the first embodiment, the input unit is in the form of a touch screen placed in covering relation to the display unit  62 . The touch screen employs as its detecting system an electrostatic capacitance system, a resistance film system, a surface acoustic wave system, an ultrasonic system, an infrared system, an electromagnetic induction system, or a load detecting system. The wireless communication unit is connected so as to be able to receive the reporting signal  200  transmitted from the transmitter  30  of the water leakage detector  1 . 
     When the terminal apparatus  60  receives the reporting signal  200 , it displays information for distinguishing the water leakage detector  1  indicated by the reporting signal  200  on the display unit  62 . 
     According to the first embodiment, a plurality of water leakage detectors  1  may be installed on the floors  101  of a plurality of installation sites  100  in a building, and the terminal apparatus  60  may receive reporting signals  200  transmitted from the transmitters  30  of the water leakage detectors  1 . In this case, the terminal apparatus  60  displays a plan of the building to the display unit  62  and further displays the installation sites  100  on the plan of the building of the water leakage detectors  1  from which the reporting signals  200  have been received. The terminal apparatus  60  and the water leakage detectors  1  jointly make up a water leakage detecting system  63  for detecting a water leakage in the building as illustrated in  FIGS. 2, 3, and 4 . In  FIGS. 2, 3, and 4 , only one of the water leakage detectors  1  is illustrated and the other water leakage detectors  1  are omitted from illustration. 
     The water leakage detector  1  of the configuration described above is installed on the floor  101  of the installation site  100 . When the positive electrode  21  and the negative electrode  22  contact water  110  that has leaked, the water cell  20  supplies electric power to the transmitter  30 , thereby detecting the water  110  that has leaked. Upon detection of the water  110  that has leaked, the water leakage detector  1  supplies electric power from the water cell  20  to the transmitter  30 , which transmits a reporting signal  200  to indicate to the terminal apparatus  60  that the water leakage detector  1  has detected the water  110  that has leaked. 
     With the water leakage detector  1  according to the first embodiment described above, when the water cell  20  contacts the water  110  that has leaked, the water cell  20  generates electric power by generating electromotive forces between the positive electrode  21  and the negative electrode  22 , and the transmitter  30  transmits a reporting signal  200  by using the electric power generated by the water cell  20  as a power source. Therefore, the water leakage detector  1  can detect water that has leaked into the installation site  100  in the building without being supplied with electric power from a commercial power supply or a direct current (DC) power supply such as a battery. As a result, inasmuch as the water leakage detector  1  can detect water that has leaked into the installation site  100  in the building without being supplied with electric power from a commercial power supply or a DC power supply such as a battery, the water leakage detector  1  is advantageous in that it restrains itself from becoming unable to detect the water  110  that has leaked. 
     Further, since the water leakage detector  1  is able to detect water that has leaked into the installation site  100  in a building without being supplied with electric power from a commercial power supply or a DC power supply such as a battery, the water leakage detector  1  is free from limitations that would otherwise be imposed on the installation site  100  by the supply of electric power, the degree of freedom of the installation site  100  is very high, and the water leakage detector  1  does not run the risk of suffering from a battery deterioration and a battery energy loss. 
     As the water leakage detector  1  can establish a reporting signal  200  uniquely to the transmitter  30 , i.e., the water leakage detector  1 , the water leakage detector  1  can acquire information representing the position or the like of the installation site  100  where a water leakage has been detected by receiving the reporting signal  200  with the terminal apparatus  60 . Further, even if many water leakage detectors  1  are installed in a building as they can be installed with ease, it is possible to recognize where a water leakage is occurring in the building. 
     Second Embodiment 
     A self-powered water leakage detector according to a second embodiment of the present invention will hereinafter be described with reference to  FIGS. 6 through 8 .  FIG. 6  illustrates in perspective a configuration example of the self-powered water leakage detector according to the second embodiment.  FIG. 7  illustrates in block form a configuration of the self-powered water leakage detector illustrated in  FIG. 6 .  FIG. 8  illustrates in side elevation the self-powered water leakage detector illustrated in  FIG. 6 . Those parts in  FIGS. 6, 7, and 8  which are identical to those according to the first embodiment are denoted by identical reference characters, and their description will be omitted hereinbelow. 
     A self-powered water leakage detector (hereinafter simply referred to as “water leakage detector”), denoted by  1 - 2  in  FIGS. 6 through 8 , according to the second embodiment is similar to the water leakage detector  1  according to the first embodiment except that it includes an LED unit  40  as illustrated in  FIGS. 6, 7, and 8  and the case  10  is made of a transparent or semitransparent material. 
     The LED unit  40  is housed in the case  10  and fixed to the case  10 . The LED unit  40  includes at least one LED. The LED unit  40  is electrically connected to the positive electrode  21  and the negative electrode  22  of the water cell  20 . When the LED unit  40  is supplied with electric power generated by the water cell  20 , the LED unit  40  turns on the LED thereof by using the supplied electric power as a power supply. 
     The water leakage detector  1 - 2  of the configuration described above according to the second embodiment is installed on the floor  101  of the installation site  100 . When the positive electrode  21  and the negative electrode  22  contact water  110  that has leaked, the water cell  20  supplies electric power to the transmitter  30 , which transmits a reporting signal  200  to indicate to the terminal apparatus  60  that the water leakage detector  1 - 2  has detected the water  110  that has leaked, as with the first embodiment. Further, when the positive electrode  21  and the negative electrode  22  contact water  110  that has leaked, the water leakage detector  1 - 2  according to the second embodiment supplies electric power from the water cell  20  to the LED unit  40 , turning on the LED thereof. 
     With the water leakage detector  1 - 2  according to the second embodiment described above, when the water cell  20  contacts the water  110  that has leaked, the water cell  20  generates electric power by generating electromotive forces between the positive electrode  21  and the negative electrode  22 , and the transmitter  30  transmits a reporting signal  200  by using the electric power generated by the water cell  20  as a power source. Therefore, as with the first embodiment, the water leakage detector  1 - 2  can detect the water that has leaked without being supplied with electric power from a commercial power supply or a DC power supply such as a battery. As a result, the water leakage detector  1 - 2  is advantageous in that it restrains itself from becoming unable to detect the water  110  that has leaked. 
     Further, since the water leakage detector  1 - 2  according to the second embodiment includes the LED unit  40  that turns on the LED by using electric power generated by the water cell  20  when electromotive forces are generated between the positive electrode  21  and the negative electrode  22  upon contact with the water  110  that has leaked, the water leakage detector  1 - 2  is further advantageous in that it allows the user to find where a water leakage is occurring in the building even in the dark by viewing the LED unit  40  of the water leakage detector  1 - 2 . 
     Third Embodiment 
     A self-powered water leakage detector according to a third embodiment of the present invention will hereinafter be described with reference to  FIGS. 9 through 11 .  FIG. 9  illustrates in plan a configuration example of the self-powered water leakage detector according to the third embodiment.  FIG. 10  illustrates in block form a configuration of the self-powered water leakage detector illustrated in  FIG. 9 .  FIG. 11  illustrates in side elevation the self-powered water leakage detector illustrated in  FIG. 9 . Those parts in  FIGS. 9, 10, and 11  which are identical to those according to the first embodiment are denoted by identical reference characters, and their description will be omitted hereinbelow. 
     A self-powered water leakage detector (hereinafter simply referred to as “water leakage detector”), denoted by  1 - 3  in  FIGS. 9 through 11 , according to the third embodiment is similar to the water leakage detector  1  according to the first embodiment except that it includes a water leakage detecting band  50  having a pair of electrically conductive wires  51  and a current detector  52  as a sensor, electric power generated by the water cell  20  is supplied to the current detector  52  and the electrically conductive wires  51 , and when the current detector  52  detects a short circuit between the electrically conductive wires  51 , the transmitter  30  transmits a reporting signal  200 . 
     The electrically conductive wires  51  of the water leakage detecting band  50  are insulated from each other. According to the third embodiment, the electrically conductive wires  51  are disposed on an outer surface of the case  10  and spaced from each other in thicknesswise directions of the case  10 . The electrically conductive wires  51  are supplied with electric power generated by the water cell  20 . The electrically conductive wires  51  are electrically connected to the current detector  52 . When each of the electrically conductive wires  51  contacts water  110  that has leaked into the installation site  100 , a short circuit is caused between the electrically conductive wires  51  supplied with the electric power generated by the water cell  20 . 
     The current detector  52  detects the short circuit between the electrically conductive wires  51  that is caused by the water  110  that has leaked. The current detector  52  operates by using the electric power generated by the water cell  20  as a power supply. When the current detector  52  detects the short circuit between the electrically conductive wires  51 , it repeatedly transmits a signal indicating the short circuit between the electrically conductive wires  51  to the transmitter  30 . According to the third embodiment, the current detector  52  is constructed as a dedicated processing circuit, i.e., a piece of hardware, such as a single circuit, a composite circuit, a programmed processor, or parallel-programmed processors. 
     According to the third embodiment, when the transmitter  30  receives the signal indicating the short circuit between the electrically conductive wires  51  from the current detector  52 , the transmitter  30  repeatedly transmits the reporting signal  200  by using the electric power generated by the water cell  20  as a power supply. According to the third embodiment, unless the transmitter  30  receives the signal indicating the short circuit between the electrically conductive wires  51  from the current detector  52 , the transmitter  30  does not transmit the reporting signal  200  even though it is supplied with the electric power from the water cell  20 . 
     With the water leakage detector  1 - 3  of the above configuration according to the third embodiment, the water cell  20  generates electric power when the positive electrode  21  and the negative electrode  22  contact water  110  that has leaked into the installation site  100 . Then, the water cell  20  supplies the generated electric power to the transmitter  30 , the current detector  52 , and the electrically conductive wires  51 . When each of the electrically conductive wires  51  contacts the water  110  that has leaked into the installation site  100 , a short circuit occurs between the electrically conductive wires  51 , and the current detector  52  detects the short circuit between electrically conductive wires  51  and repeatedly transmits the signal described above to the transmitter  30 , which repeatedly transmits a reporting signal  200 . 
     The transmitter  30  transmits the reporting signal  200  by using the electric power generated by the water cell  20  upon contact with the water  110  that has leaked. Therefore, as with the first embodiment, the water leakage detector  1 - 3  according to the third embodiment can detect the water  110  that has leaked without being supplied with electric power from a commercial power supply or a DC power supply such as a battery. As a result, the water leakage detector  1 - 3  is advantageous in that it restrains itself from becoming unable to detect the water  110  that has leaked. 
     With the water leakage detector  1  according to the first embodiment, once the positive electrode  21  and the negative electrode  22  have been wet with water, a voltage tends to remain on the water cell  20  even if water droplets are wiped out, and the transmitter  30  tends to transmit a reporting signal  200 . The water leakage detector  1 - 3  according to the third embodiment, however, includes, separately from the water cell  20 , the water leakage detecting band  50  having the electrically conductive wires  51 , and the current detector  52  for detecting a short circuit between the electrically conductive wires  51  of the water leakage detecting band  50 . With the water leakage detector  1 - 3  according to the third embodiment, the transmitter  30  does not transmit a reporting signal  200  even though it is supplied with the electric power from the water cell  20  unless the transmitter  30  receives a signal indicating a short circuit between the electrically conductive wires  51  from the current detector  52 . 
     As a result, as the water leakage detector  1 - 3  according to the third embodiment uses the water cell  20  as a power supply that generates electric power by using water  110  that has leaked, and transmits a reporting signal  200  only when the water leakage detecting band  50  detects a water leakage, so that the water leakage detector  1 - 3  can restrain the transmitter  30  from continuously transmitting a reporting signal  200  due to a remaining voltage on the water cell  20 . 
     The present invention is not limited to the details of the above described preferred embodiments. The scope of the invention is defined by the appended claims and all changes and modifications as fall within the equivalence of the scope of the claims are therefore to be embraced by the invention.