Patent Publication Number: US-7900647-B2

Title: Water leak detection and prevention systems and methods

Description:
PRIORITY CLAIM 
     This application is a continuation of U.S. patent application Ser. No. 11/099,351, Filed Apr. 5, 2005, now U.S. Pat. No. 7,306,008, and claims the benefit of U.S. Provisional Application No. 60/559,543 filed Apr. 5, 2004 and of U.S. Provisional Application No. 60/572,699 filed May 20, 2004, the disclosures of which are incorporated in their entirety herein by reference. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to detecting and preventing accidental water leaks inside of homes and businesses. 
     BACKGROUND OF THE INVENTION 
     Water leaks in homes and businesses cause a tremendous amount of damage to structures and contents. Leaks generally occur from a burst water pipe or leaking faucets or water using appliances. If an occupant is present and the leak is easily visible, water damage can often be prevented. However many leaks occur behind cabinets and in the walls so that even if an occupant is present, the leaks may not be discovered until a very substantial amount of damage has been caused. It is not uncommon for an undetected leak to literally create havoc and require major reconstruction to return the building to a usable state. Moreover, leaks induce the growth of hazardous mold. 
     A number of published articles relate to an increasing rate of claims against insurance companies for water damage claims and the resultant increase in cost and difficulty in obtaining insurance for homes and businesses in which water leakage claims have previously been made. See, e.g., in  Money  magazine, April 2003, the article by Lisa Gibbs and the web sites: http://www.iii.org/media/facts/statsbyissue/homeowners/ http://www.rmiia.com/Homeowners/water_damage.htm. 
     SUMMARY OF THE INVENTION 
     One aspect of embodiments of this invention is to prevent any substantial leak in a home or business by disconnecting the home or business building from the high pressure water in the water main during those periods of time when there is no water demand within the home or business building. In most buildings, in fact, such periods are the majority of the time that the building is occupied. 
     Another aspect of embodiments of this invention is to continuously monitor and detect any leak of consequence in the home or building during those periods of time when the home or business building is disconnected from the high pressure water in this water main. 
     Another aspect of embodiments of this invention is to prevent the flow of water into a building by blocking water flow from the main water supply unless two conditions are met:
         1. Water is actually demanded at a normal water outlet (e.g., faucet, toilet, shower, dishwasher, clothes washer, refrigerator, and humidifier).   2. No leaks in the buildings water system (e.g., cracks in water lines, loose fittings or pipes, ruptured hoses in appliances) has been detected while the water flow from the main has been blocked.       

     An aspect of embodiments of this invention is to continually monitor and detect any leak of consequence in this home or building when no water is flowing in the building&#39;s water pipes. 
     Still another aspect of embodiments of this invention is to prevent substantial damage when the occupant or an appliance inadvertently demands water from the main when in fact, such demand is due to the forgetfulness of the occupant to turn off a faucet or failure of an appliance to turn off its demand for water. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of one embodiment of a water leak detection and prevention system. 
         FIG. 2  is a flow chart showing the operation of the embodiment of  FIGS. 1-6 . 
         FIG. 3  is a detailed circuit schematic for the water leak detection and prevention system of  FIG. 1 . 
         FIG. 4  is a perspective view of an embodiment in which some or all of the appliances have a wireless connection to the water leak detection and prevention control system. 
         FIG. 5  is a detailed circuit schematic for the leak detection and prevention system of  FIG. 4 . 
         FIG. 6  is a detailed circuit schematic for the leak detection and prevention system, including a smoke or fire alarm override. 
         FIG. 7  is a detailed circuit schematic for a leak detection and prevention system including a timer override control. 
         FIG. 8  is a flow chart showing the operation of the embodiment of  FIG. 17 . 
         FIG. 9  is a front view of a faucet having an electrical on-off switch. 
         FIG. 10  is a side view of the faucet of  FIG. 7 . 
         FIG. 11  is a cutaway view of the faucet of  FIGS. 7 and 8 . 
         FIG. 12  is a top view of another embodiment of a faucet having an electrical on-off switch. 
         FIG. 13  is a side view of the faucet of  FIG. 12 . 
         FIG. 14  is a front view of a faucet having an embodiment of a faucet having a small red light to indicate when the faucet is turned on. 
         FIG. 15  is a side view of the faucet of  FIG. 14 . 
         FIG. 16  is a side view of a modified faucet having a small red light to indicate when the faucet is turned on. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The conventional home and business is continuously at risk for water leaks. Such leaks can be disastrous and expensive. In the conventional home or business (not shown), the cold and hot water pipes extend throughout the structure and are continuously connected to the water main supplying water under pressure. As a result, any ruptures in the water system will instantly result in a water leak. Moreover, since the water pipes are often hidden within the walls of the building, it may take, even in an occupied home or business building, several hours or even days for a leaking pipe or joint to manifest itself, such that by the time of discovery, substantial damage can be done not only to the building and furnishings, but also create a serious mold problem. 
     In the embodiment of  FIG. 1 , however, the risk of water damage due to a leak or leaks in the plumbing is very substantially reduced. 
       FIG. 1  illustrates a representative home or business  1000  plumbed for several water using appliances, such as, for example, a sink  10 , toilet  15 , hot water heater  20 , clothes washer  25 , bathtub  30  and bath sink  31 . Each of these appliances is typically connected to a cold water pipe  35 . A hot water pipe  40  connected to the outlet of the hot water heater  20  is typically connected to all of the other appliances, except the toilet. 
     Between the cold water pipe  35  and the main water supply  45  is an electric shutoff valve  50 . Valve  50  is located either within this building or outside of the building close to the main  45 . The fail safe mode for this valve is its closed, shutoff state, i.e., if the electricity to the building is off for any reason, the only water in the cold water and hot water pipes  35 ,  40  is the water remaining from when the valve  50  was last turned off. 
     In normal operation, the electrical shutoff valve  50  is opened by control circuit  1001  only when a water valve within the house or business is deliberately actuated by an individual opening a faucet or by operation of an electrical appliance connected to either one or both of the hot water and cold water pipes  35 ,  40 . Referring to  FIGS. 1 and 3 , each water-using device in the building includes an on/off switch  55   a,    55   b,    55   c  . . .  55   f  connected to a low voltage network  70 . Thus, the hot and cold bath faucets  60 ,  65  are connected by low voltage network wires  70  to the control circuits shown in  FIG. 3 . Each water-using appliance typically already has an electrically actuated inlet valve. For existing appliances, it is advantageous to connect the low voltage network  70  to the control circuits of each electrical appliance so that each time the dishwasher, clothes washer, etc. demands water by opening its water inlet valve, the signal generated by the appliance not only opens the inlet valve of the particular appliance, but also functions as one of the switches  55   a,    55   b,    55   c  . . .  55   f.    
     In the embodiment illustrated in  FIGS. 1 ,  2  and  3 , a wired connection is made to each existing water-using electrical appliance, whereas, in another embodiment described below and illustrated in  FIGS. 4 and 5 , wireless signals are sent from some or all of the appliances to avoid the necessity of hardwiring an existing home or business building. The switches  55   a,    55   b,    55   c  . . .  55   f  are electrically connected in parallel so that closure of any switch results in the delivery of electrical current from a low voltage source  71  (typically 12 volts) to relay switch  75 . Flow of current to relay  75  causes the relay to be energized and close switch contacts  80 . Closure of contacts  80  completes the circuit from line voltage  81  causing the shutoff valve  50  to turn on. Water then flows from the main  45  to the demanding appliance. Thus, whenever water is demanded in the home or business, an electrical switch  55   a,    55   b,    55   c  . . .  55   f  is closed in the demanding appliance to cause the normally closed electrical shutoff valve  50  to open and deliver water from the main  45  to the demanding appliance. 
     When water is no longer demanded by a particular appliance, the switch  55   a - f  associated with this appliance is opened, either when the user closes a faucet or the clothes washer or other operating appliance closes its water inlet valve. As a result, when no main water is needed, all of the appliance switches  55   a - f  will be in their open state and no current will be delivered to the electrical shutoff valve  50 , thereby disconnecting the main water supply from the home or business and preventing the main water pressure from causing a water leak in the home or business while this valve  50  is shut. 
     The embodiment of the invention illustrated in  FIGS. 1 ,  2  and  3  also provides for automatically detecting a leak in the home or business by detecting a decrease in water pressure within the water pipes of the home when the shutoff valve has been closed. Referring now to  FIGS. 1 and 3 , a pressure sensor  85  is incorporated in the water line between all of the water-using appliances and the electrical shutoff valve  50 . This pressure sensor  85  continuously monitors the pressure in the water line  35  during the periods of time that the electric shutoff valve  50  is closed. With no water pressure being supplied from outside the home or business, any decrease in the water pressure within the business or home water pipes will necessarily be caused by water leakage from either the cold water pipe  35 , the hot water pipe  40  or an appliance connected to a water pipe somewhere in the home or business. 
     Referring now to  FIG. 3 , pressure sensor  85  is connected to a normally closed relay contacts  90  and to a normally open contacts  95 . When the pressure sensor detects a drop in water pressure in the home or business water pipes, it opens the normally closed relay contacts  90  and closes the normally closed relay switch  95 . Opening relay contacts  90  opens the circuit to the electrical shutoff valve  50 . As a result, any demand for water in the house or business (e.g., opening a faucet) after detection of any leak will fail to actuate value  50  so that no water flows into the home or business from the water main. Actuation of the relay contact  95  to the closed position also closes the electrical circuit to an alarm located in the home or business. Advantageously, this alarm includes both a warning light and audible alarm  100 . Thus detection of a water leak results in (a) cutting off power to shutoff valve  50 , thus preventing any water flow into the home or business and (b) engaging either or both warning light and alarm  100 . The light and alarm alert the occupant(s) of the building to a leak in their water system. In some systems, the signal may also, for example, engage an external communication to a home security business so that an unoccupied home or business may be inspected. 
     If upon investigation the leak is a minor one such as a slowly dripping faucet, the occupant can decide to still allow water to flow into the building. If so, they simply close a manual override switch  105  which allows the water valve  50  to be energized each time a faucet or appliance demanding water is actuated. 
     Pressure sensor  85  is automatically cleared or reset each time the electrical shutoff valve  50  is energized. Thus, as shown in  FIG. 3 , the pressure sensor reset circuit is connected in parallel to the water valve  50  so as to be reset each time the water valve  50  is actuated. 
     The embodiment of  FIGS. 1 and 3  described above illustrates a system in which a low voltage network  70  is hardwired. In the embodiment of  FIGS. 4 and 5 , each water-using appliance such as the sink  10 , toilet  15 , hot water heater  20 , clothes washer  25  and bathtub  30  includes a wireless link to the water detection and leak prevention circuitry. The embodiment of  FIG. 4 and 5  is particularly advantageous for retrofitting existing homes and business buildings since it eliminates the need to hardwire a low voltage network throughout the home or business. In the embodiment of  FIGS. 4 and 5 , each faucet and each electrical appliance is fitted with a wireless signal transmitter  110 . Typically, such radio frequency (rf) units  110   a,    110   b,    110   c  . . .  110   f  are small, inexpensive battery-powered units. An rf receiver  115  is located proximate to and directly connected to the relay actuating the electrical shutoff valve  50 . Upon receipt of a wireless signal from a transmittal  110   a,    110   b,    110   c  . . .  110   f,  the receiver  115  causes relay  116  to close switch contacts  117  and delivers current to water valve  50 . 
     The operation of the system illustrated in  FIGS. 1 ,  3  and  5  is further illustrated by the flow chart of  FIG. 2 . 
     For existing construction, the building&#39;s water supply can be fitted with either a hardwire-controlled or a wireless signal-controlled electric shutoff valve  50 . If the owner of an existing building chooses to have a hardwired system, then all faucets will be replaced with signal sending faucets and all other water-using appliances (dishwasher, clothes washer, ice maker, humidifier, etc.) will be spliced into so that all faucets and other devices will be wired into the system. The second option of installing a wireless signal-controlled system in an existing building does not require as much labor and expense as the installation of a hardwired system. With the wireless signal-controlled shutoff valve  50 , faucets and toilets are fitted with signal sending devices that send wireless signals (much like a garage door opener) when water is demanded. All other devices (dishwasher, clothes washer, ice maker, humidifier, etc.) are spliced into and also fitted with wireless signal sending devices. The signal sent by these signal sending devices is received by the receiver  115 , opening the valve and allowing water into the building. The wireless signal sending devices for the faucets and toilets are small in size and battery operated. The wireless signal sending devices for all other devices (dishwasher, clothes washer, ice maker, humidifier, etc.) are advantageously wired into the existing electrical system, eliminating the need for battery operation. 
     It will be apparent that other embodiments can include both hardwired and wireless components to cause closure of the circuit to deliver power to water valve  50 . 
     Each wireless signal sending device (on faucets, toilets, and other devices) has advantageously a small red light (see light  120  in  FIG. 15 ) that lights whenever a signal is being sent by the device. This red indicator light is intended to alert building occupants to any false signals being sent by the signal sending devices, which would unintentionally open the shutoff valve  50  exposing a building to accidental water leakage or discharge. 
     The embodiment of  FIG. 6  illustrates a hardwired embodiment for buildings having a built-in sprinkler system. Although the system shown is hardwired to each faucet and water using appliance it will be apparent that the system can be a wireless system or a combination hardwired and wireless system. An override circuit includes one or more fire alarm sensor  120  or smoke alarm sensor  125  connected by a wired or wireless link to a fire/smoke alarm relay  130 . When fire or smoke is detected by the sensor  115  or  120 , normally open relay  130  is energized to close contacts  130 . As a result, the circuit connecting line voltage  81  to shutoff valve  50  is closed so as to continuously connect the water shutoff valve to electricity to ensure that water from the main  45  can freely flow to the sprinklers within the building. 
       FIGS. 7 and 8  illustrate an embodiment which prevents substantial flooding in a home or business building when a user forgetfully leaves a faucet on or an appliance control such as the timer control in a dishwasher or clothes washer fails to close valve  50 . A timer  150  is automatically triggered each time the relay  75  is activated to start timing a preset interval. Timer  150  is preset to a time limit sufficient for the normal time cycle of an appliance or the normal time that a faucet is open for washing or bathing. A typical setting for timer  100  is a one hour preset time period. At the end of this his preset time interval, timer  150  opens normal closed relay contacts  155  to disconnect the water valve  50  from line voltage  81 , thus shutting off the supply of water into the home. As shown, timer  150  is also advantageously connected to close relay contacts  55  to cause alarm to sound and notify the occupant of the building. 
     Advantageously, the timer  150  will automatically reset when the switch  55   a - f  is located and opened. Alternatively, the timer may include a manual override to reset it if a period of water inflow from the main  45  is needed for a longer period than the time that has been preset into timer  150 . 
     Different embodiments of signal sending faucets will now be described.  FIGS. 9 ,  10  and  11  illustrate a design compatible with faucets that operate by means of a handle being lifted. Another design intended to be compatible with faucets that operate by means of a rotating handle as shown in  FIGS. 12 and 13 . Both faucets types (lifted handle and rotating handle) can be fitted with components designed to send wireless signal whenever the faucet is opened (see  FIGS. 14 ,  15  and  16 ), in lieu of the hardwired design.  FIGS. 9 through 11  illustrate the basic design of the lifted handle signal sending faucet. The handle  170  of the faucet is mounted on a faucet base  175  that houses the normal parts needed to provide a flow of water. The top section of the base is double-walled and insulated, creating a hollow section between the two walls. Inside the hollow section, at the front of the faucet, an electrical switch  55  is mounted. The movable top part of that protrudes out of the front of the faucet base. Any time there is no water demand, the faucet handle is in the down position. Having the handle in the down position pushes in the protruding button and opens a switch  55 . When the faucet handle is lifted (water is demanded), the protruding button pops out of the faucet base, closing the switch contacts and closing the electrical circuit shown in  FIG. 3 . This closes the circuit to water valve  50  and allows water to flow into the building. 
       FIGS. 12 and 13  illustrates the basic design of a rotating handle signal sending faucet. The handle  180  of the faucet is mounted on a faucet valve that allows water to flow whenever the faucet handle is rotated. The outer section  185  of the faucet handle is double-walled and insulated, creating a hollow section between the two walls. Inside the hollow section is a horizontally mounted tapered section  190 . Whenever the faucet handle is turned to the “off” (no water demand) position, the tapered section  190  moves towards and pushes down a popup button  195  also located inside the hollow section of the faucet handle. The button  195  and associated switch  55  is permanently mounted and does not rotate with the faucet handle. The button  195  engages a switch  55 . When the faucet handle is turned to the “on” (water is demanded) position, the tapered section  190  rotates away from the popup button  195 , allowing the button to pop up into the hollow section of the faucet handle. The button popping up closes the contacts of switch  55  and closes the electrical circuit to water valve  50  allowing water to flow into the building to the faucet. 
       FIGS. 14 ,  15  and  16  illustrates lifted handle and rotating handle faucets fitted with signal sending devices that send wireless signals (much like a remote controlled garage door opener) when water is demanded. For both lifted handle and rotating handle faucets, the design consists of two parts—the signal transmitter  110  and the actuator  210 . For both lifted handle and rotating handle faucets, the signal transmitter  110  is advantageous mounted onto the base  215  of the faucet by means of a mounting bracket that the piece snaps into. This part contains the power (a small battery) needed to send a signal, and is a sealed component. Whenever the battery in this part becomes too low to operate, the signal sending piece is snapped out of its mounting bracket and a new signal piece with a fresh battery is snapped in. Keeping this piece sealed (and not allowing simple battery replacement) avoids potential problems caused by water contamination. The signal transmitter advantageously has a small red light that illuminates whenever a signal is sent. This light serves two purposes. It alerts the user to a signal being sent (allowing the user to detect any false signals), and also alerts the user to a low battery by means of a weak light. Whenever water is demanded (faucet handle is lifted or rotated) the signal transmitter  110  (bottom part) and the actuator piece (top part) are separated. When the top and bottom parts are separated, e.g., when the faucet is turned on, the transmitter  110  is activated, illuminating the small red light  120  and sending a wireless signal to the remote receiver  115  shown in  FIG. 5  to cause water valve  50  to open, allowing water to flow into the building. 
     It will be understood that the embodiments of the invention are not limited or restricted to any particular form of faucet constructed with an integral on-off switch. Representative prior art faucets having an integral switch include U.S. Pat. Nos. 4,092,025; 2,777,675; 5,911,240; 4,856,121. 
     The above presents a description of the best mode contemplated for carrying out water leak detection and prevention systems and methods in such full, clear, concise and exact terms as to enable any person skilled in this art to which it pertains to make and use these systems and methods. These systems and methods are, however, susceptible to modifications and alternate constructions from that discussed above that are fully equivalent. Consequently, these systems and methods are not limited to the particular embodiments disclosed. On the contrary, these systems and methods cover all modifications and alternate constructions coming within the spirit and scope of the present invention.