Abstract:
A latched, spring loaded valve having a water sensor and an activation mechanism shuts off water supply, when a water leak is detected, to specific application as cloths washing machines, dishwashing machines, sinks, toilets, and refrigerators equipped with ice makers. The shutoff valve system with leak detector has a sealing member movable with a valve body between an open position and a closed position wherein the sealing member blocks fluid flow.

Description:
BACKGROUND OF INVENTION 
     1. Field of Invention 
     This invention relates to a valve system that detects the presence of a water leakage and turns off an associated valve in order to stop the flow of the water, thus avoiding significant property damage. More particularly the invention pertains to such applications as clothes washing machines, dishwashing machines, toilets, sinks, and refrigerators equipped with ice cube makers, which occasionally are the source of water leaks due to broken hoses, faulty water level detectors, and the like. 
     Insurance companies have recently disclosed that water damage claims exceed fire damage claims. This emphasizes the need for the preventive measures that are provided by this invention. Since the invention does not require any electronic circuitry or complex mechanical devices to function, it provides a cost-effective and reliable means of turning off the source of water leakage. 
     2. Description of Prior Art 
     There are numerous water leak detection systems, most of which involve the use of an electronic means for sensing the presence of fluids such as water. The sensor elements of such systems typically involve measuring the conductivity of the water and use such a detection means to energize a solenoid or other such device to turn off an associated water valve. Not only does the electronic circuitry add cost and reduced reliability, it also requires the presence of electrical power to function. If a water leak occurs coincidentally with an electrical power outage, the valve will fail to accomplish its purpose, unless auxiliary power is supplied. 
     There are several prior art patents that provide water shutoff protection utilizing a water sensor that changes physical properties when placed in contact with water, thereby activating a valve shutoff device. Upon review it will become evident that these patents are intended for use on water heaters. Installation of such shutoff devices requires plumbing skills such as cutting into the existing water source pipe and soldering the new valve device in place or installing the necessary threaded fittings to accommodate the new valve. In many locations it would involve hiring a licensed plumber to comply with local building codes. The cost and complexity of such an installation often is a deterrent to undertaking the project. As will be seen by the following disclosure the proposed water shutoff system of the present invention is intended for use on the indicated appliances such as clothes washing machines, etc. and can be easily installed. Since no knowledge of plumbing skills is required, this invention would lend itself to do-it-yourself installation. 
     One device described in U.S. Pat. No. 2,798,503, dated Jul. 9, 1957, issued to Carver et al, utilizes a water softenable link that dissolves when coming in contact with water leaking from a water heater into an associated drip pan. As described, the cable attaching the water softenable link to the shutoff valve must be positioned directly beneath the shutoff valve so that the sofltenable link can be anchored in the drip pan. While appropriate for this installation it would not provide the flexibility to be applicable on other applications. 
     Another device described in U.S. Pat. No. 3,920,031, dated Nov. 18, 1975, issued to Maxfield provides a water shutoff device associated with a water heater application. The water detection means involves the use of a water-soluble material held in compression by a spring. The water detection means is placed in a drip pan that surrounds the base of the water heater such that, as water leaks from the faulty water heater, it will reach a level to dissolve the detection means which in turn releases a spring driven valve that is plumbed into the water supply line of the water heater. 
     Another device described in U.S. Pat. 5,632,302, dated May 27, 1997, and issued to Robert M. Lenoir, Jr. provides two different means of specifically dealing with water heater leakage. One means involves the use of an electrical sensor to detect the presence of water leakage specifically from a water heater in order to activate a solenoid to turn off an associated water valve located in the cold water input pipe of the water heater. A second described means involves the use of a thin, dissolvable strip, which is in tension, and dissolves in the presence of water thus releasing a spring mechanism which, in turn, activates a spring loaded valve specifically located in the cold water input pipe of a water heater. There are two basic drawbacks to this second means as described. First, the use of a standard ball valve in such an application requires the use of a spring-loaded valve with a very strong spring. Ball valves typically involve full contact seals such as O-rings on both the inlet and outlet sides of the rotating ball. These O-rings produce a great deal of pressure on the ball, thus requiring inordinate rotational torque to close the valve, making the valve reliability questionable. Second, the dissolvable strip as described in the invention is shown in tension. Most such materials, which might be used as described, are composed of a water soluble, crystalline structure that exhibits poor tensile strength, thus making it unreliable and subject to premature failure. As will be seen later, the present invention overcomes the above shortcomings and provides an easily installed system for water and, where applicable, non-water water systems. 
     Yet another U.S. Pat. No. 6,024,116, dated Feb. 15, 2000, issued to Almberg et al, again deals specifically with water leak detection in water heater applications. It provides a water softenable latch that, when exposed to water, will release a valve mechanism from its open to closed state thus turning off the water supply. In addition the invention turns off the gas supply to the water heater. 
     Most prior art found addresses the subject of water leak conditions as they pertain to water heaters. The following invention description pertains more specifically to use with clothes washing machines, dishwashing machines, toilets, sinks, and refrigerators equipped with ice cube makers that often use flexible hoses in their individual applications. 
     SUMMARY OF THE INVENTION 
     This invention provides a simple, reliable means of detecting and shutting off the source of most common water leaks involved with clothes washers, dishwashers, toilets, sinks, and refrigerators equipped with ice cube makers by utilizing a spring loaded shutoff valve in conjunction with a water sensor. Although the following invention description focuses primarily on those appliance applications listed above, which involve water leakage, it could likewise apply to other applications involving the use of other non-water fluids, where applicable. As will be seen later, the valve described in this invention utilizes a flow-through central element that allows water to flow through its central opening in normal operation but closes the water flow patly when activated to its closed condition. The use of this flow-through central element, in conjunction with a water sensor and activation mechanism, provides a compact, simple water shutoff device. The use of this valve does not preclude the use of other types of valves by those skilled in the art to accomplish the goals of this invention. 
     The water sensor described in this invention utilizes a water-soluble substance in a compression mode. Other methods for containing the water-soluble material, for example, in a bending, torsion, or tension mode, as devised by those skilled in the art, should not detract from the spirit of this invention. The water-soluble substance could be composed of such materials as sugar, salt, or the like. These materials exhibit relatively high strength in compression when dry and lose most if not all of that strength when exposed to a fluid such as water. As will be shown later with regard this invention, a spring maintains pressure against the water-soluble substance and will initiate a closure of the associated valve when the water-soluble substance dissolves. The substance used in several experiments has been sugar. It is very strong in compression, very soluble in water, easily shaped and inexpensive. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a typical clothes washing machine installation with water sensors and shutoff valves located in the inlets to the hose lines. 
     FIG. 1A shows an enlargement of an area of FIG. 1 to provide a more detailed depiction of the shutoff valve installation. 
     FIG. 2 shows a typical toilet installation with a water sensor and shutoff valve located at the inlet to the flexible hose line. 
     FIG. 3 shows a partial cutaway of a typical sink installation with a water sensor and shutoff valve located at the inlet to the flexible hose line. 
     FIG. 4 shows a partial cutaway of a typical refrigerator installation equipped with an automatic ice maker device, along with a water sensor and shutoff valve connected to a water source via a hose or tubing means. 
     FIG. 5 shows the external view of the shutoff valve used with hose connections on typical dishwashing machine or clothes washing machine installations. 
     FIG. 6 shows the external view of the shutoff valve used with flexible pipe and hose connections on typical toilet, refrigerators equipped with ice makers, and sink installations. 
     FIG. 7 shows a cross-sectional view of the shutoff valve used with hose connections on typical dishwashing machine or clothes washing machine installations. The valve is shown in an open condition. 
     FIG. 8 shows a top view of the shutoff valve with a partial cutaway of the valve activation mechanism when the valve is in an open condition. 
     FIG. 9 shows a top view of the shutoff valve with a partial cutaway of the valve activation mechanism when the valve is in a closed condition. 
     FIG. 10 shows a cross-sectional view of the shutoff valve of FIG. 7 with the valve shown in a closed condition. 
     FIG. 11 shows the external, top view of the water sensor assembly. 
     FIG. 11A shows an external, side-elevation view of the water sensor assembly. 
     FIG. 12 shows the top, cross-sectional view of the water sensor assembly in a latched, standby state. 
     FIG. 12A shows the top, cross-sectional view of the water sensor assembly in an activated state. 
    
    
     DETAILED DESCRIPTION 
     FIGS. 1,  1 A,  2 ,  3 , and  4  show typical installations of the water shutoff valve of the present invention. FIG. 1 shows a clothes washing machine  15  with its hot and cold water connections, Valves  14  and  14   a  represent the hot and cold water valves respectively, normally found on such appliance installations, and which supply water to the clothes washing machine  15 . Attached to these valves  14  and  14   a  are the shutoff valves  13  and  13   a  to be described herein. Hoses  18  and  18   a  provide the water connections between the shutoff valves and the hot and cold water inputs to the clothes washing machine. Cables  16  and  16   a  are used to couple the water sensor assemblies  17  and  17   a  to the shutoff valves  13  and  13   a  respectively. FIG. 1A is an enlargement of the above mentioned valve  14 , shutoff valve  13 , cable  16  and hose  18 , and is provided to visually clarify the actual connections. A typical connection used in a dish washer application is not shown since it closely resembles that used on the clothes washing machine with the exception that only one hose connection, namely the hot water line, is used. 
     FIG. 2 shows a toilet  21  with its reservoir tank  22 . A typical installation has a valve  19  that allows a means for turning on and off the source of water necessary for operation. Connected to the top outlet of valve  19  is shutoff valve  23 . Although the internal structure of valve  23  is the same as the previously mentioned shutoff valves  13  and  13   a , it differs in the fact that the hose connections of valves  13  and  13   a  are replaced by smaller, threaded connections appropriate for that installation. Hose  20  provides the necessary coupling between the top of shutoff valve  23  and the bottom of the reservoir  22 . Cable  16  provides the necessary coupling between the shutoff valve  23  and the water sensor assembly  17 . 
     FIG. 3 shows a partial cutaway view of a typical sink installation in which a sink  24  is mounted in a cabinet  27  with the associated hot and cold faucets  26 . Although the side view shows only one faucet connection, it should be understood that the other faucet connection, either hot or cold, is identical to that shown in the foreground. Valve  19 , shutoff valve  23 , cable  16 , and water sensor assembly  17 , are identical to that previously described in FIG. 2 and, hence, carry the same number designations. Hose  25  provides the necessary coupling between the top of the shutoff valve  23  and the faucet configuration  26 . 
     FIG. 4 shows a typical refrigerator  28  with a partial cutaway view of the ice cube maker  29  located within the freezer compartment. Tubing  30  connects the ice cube maker to the shutoff valve  23  that is in turn connected to the water valve  19 . Cable  16  connects the shutoff valve to the water sensor  17 . 
     FIG. 5 shows the outside structure of the shutoff valve  13  shown in FIGS. 1 and 1A. Coupling sleeve  31  is internally threaded, and independently rotatable as might be found on a standard water hose. It provides a means of fastening the shutoff valve to a standard water faucet or water pipe equipped with a hose thread Cable  16  is used to couple the shutoff valve to the associated water sensor assembly, to be described in detail later. Threaded outlet  33  for the shutoff valve  13  provides a means for connecting a hose to the shutoff valve. Such a hose is described in FIG. 1 as items  18  and  18   a.    
     FIG. 6 shows the outside structure of the shutoff valve  23  shown in FIGS. 2-4. As previously mentioned, the only difference between this shutoff valve  23  and that of shutoff valves  13  and  13 a is the inlet and outlet connection means. A small, internally threaded and rotatable sleeve  34  provides a means of connecting the shutoff valve  23  to a water source. The standard installation would typically attach the inlet of the shutoff valve  23  to the threaded outlet of a valve  19 , Threaded outlet  35  provides a means of attaching the flexible hose  20 ,  25 , and  30  to the appropriate appliances as shown in FIGS. 2,  3 , and  4  respectively. 
     FIG. 7 is a cross-sectional view showing the internal structure of the shutoff valve  13  in an open condition allowing water flow through the valve as indicated by the flow arrows. As previously mentioned, threaded coupling sleeve  31  is used to attach the shutoff valve  13  to a faucet or other properly threaded water source. Washer  36  provides a water seal between the input water source and the valve-input sleeve  37 . The valve outer housing is comprised of members  38  and  39  and provides an enclosure that is moveable with respect to the valve-input sleeve  37 . It should be noted that members  38  and  39  are press fit or threaded together at points  41  to form an integral unit. Member  38  appears three times in FIG. 7 to clarify that it represents a housing that surrounds the valve-input sleeve  37 . The position of the valve-input sleeve  37  relative to the enclosure, members  38  and  39 , is such that spring  42  is compressed to its shortest axial length. O-rings  54  and  55  provide a primary and secondary moveable water seal respectively between sleeve  37  and member  39 . Sealing member  56  is held in place by cap nut  57  that is threaded onto the end post  58  and forms a scal when the valve is closed as will be described later. Sealing member  56  can be an O-ring, a gasket, or any other element that provides a seal when the valve is closed. A flexible hose ( 18  and  18   a  in FIG. 1) from an appropriate appliance such as a clothes washing machine can be attached to threaded outlet  33 . Such an arrangement allows the moveable valve elements to move with the fluid flow or to the right relative to the fixed elements  31 ,  36  and  37 . In order to prevent the spring  42  from pushing members  38  and  39  to the right relative to sleeve  37  a pin  44  and latch  43  lock these items in the position shown. As will be seen later, latch  43  rotates about pivot pin  45 . Because FIG. 7 is a sectional view of the valve assembly latch  43  appears to be two separate entities but in fact it is a single item as will be seen in FIG.  8 . Cover  50  protects the latch mechanism. 
     FIG. 8 is a top view of the shutoff valve  13  with a partial cutaway view to display the inner parts of the latching system. As can now be clearly seen latch  43  is anchored at pivot pin  45 . Surface  59  of latch  43  restricts any right directed movement of threaded outlet  33  and members  38  and  39  relative to threaded coupling sleeve  31  and valve input sleeve  37 . Since sleeves  31  and  37  are fastened to a faucet or appropriate valve they should be considered fixed in position.  47  is a vertical extension of latch  43 . Spring  52  is attached to extension  47  and anchored at pin  51 , thus applying a small force necessary to retain or return the latch  43  in the position shown Cable  16  has an internal wire or other appropriate flexible element  48  that is used to transmit the force from the water sensor  17  to the latch vertical extension  47 . This force will be necessary to activate the latch mechanism when valve closure is required. Item  53  clamps around wire  48  to allow the wire to pull on vertical extension  47  and thus the latch  43  when valve closure is required. The water sensor unit will be described later. 
     FIG. 9 is a top view of the shutoff valve  13  with a partial cutaway view to display the inner parts of the latching system when the valve is in a closed condition, which happens when a water leak is detected. It can be seen that wire  48  has pulled the vertical extension  47  and thus latch  43  away from pin  44  by rotating about pivot pin  45 . Items  33 ,  39 , and all items physically connected to these items then move with the fluid flow or to the right relative to items  31 ,  37 , and pin  44  as a result of the force of spring  42  expanding as shown in FIG.  10 . 
     FIG. 10 is a cross-sectional drawing showing the internal structure of the shutoff valve  13 , which is now in the closed condition. Spring  42  has expanded, providing the force necessary to move the valve to the closed position. It can be seen that items  38 ,  39  and all physically connected items have moved to the right relative to items  31  and  37 , allowing O-ring  56  to seat against the valve surface  60 . O-ring  56  is now the primary seal and water flow ceases. 
     To reset the shutoff valve system to the open position force, such as with a hand, is applied to threaded outlet  33  to move it against the direction of fluid flow or to the left against the pressure of expanded spring  42 . This allows spring  52  to pull extension  47  to the position shown in FIG. 8 with the pin  44  against latch surface  59 . Water can then flow as shown in FIG.  7 . 
     FIG. 11 is a top, external view of the water sensor assembly  17 . As will be seen later, the enclosure  61  contains a spring and plunger mechanism. Cartridge  62  contains a water-soluble element and is designed to be a replaceable unit attached to the enclosure  61  by means of two clip arms  63  and  64 . Openings  65  are provided to allow the passage of fluid, such as water, into the cartridge  62 . Cable  16  is as shown in FIGS. 1,  2 ,  3 , and  4  and houses a wire  48  or other appropriate material that transmits the necessary force to pull the latch  43  from its position in FIG. 8 to its position in FIG. 9 when a water leak is detected. FIG. 11A is an elevation side view of the water sensor assembly  17  to give some perspective as to the thickness of the assembly, which could be typically one quarter of an inch. The thickness of the wall of the cartridge  62  containing the water-soluble element would be on the order of thirty thousands of an inch. The thinness of this wall allows entry into the cartridge  62  of very low water levels that might accumulate on the floor or other adjacent surface as a result of water leakage. 
     FIG. 12 is a top, cross-sectional view of the water sensor assembly  17 . Cartridge  62  contains the water-soluble element  75 . Plate  74  is a thin, rigid element, which distributes the force from plunger  72  to the surface of the fluid-soluble element  75 . Springs  70  and  71  apply an axial force on plunger  72 . Tapered surfaces  66  and  67  are provided to allow the clip arms  63  and  64  to slide and bend during engagement of cartridge  62  with enclosure  61 . When the hook portion of the clip arms  63  and  64  reach the latch surfaces  68  and  69  respectively they will snap into a position shown, thus retaining the engagement of cartridge  62  with the enclosure  61 . Clamp  73  is fastened to the end of wire  48  and rests against the inner slide surface of plunger  72 . It can now be seen that, in the configuration of FIG. 12, the water sensor assembly  17  is in a latched state and ready to be triggered when a fluid such as water dissolves the water-soluble element  75 . 
     FIG. 12A is a top, cross-sectional view of the water sensor assembly  17  in the triggered state. A typical water leakage condition causes water to accumulate on the floor around the appliance. Since the water sensor would be located adjacent to the appliance it would come in contact with the accumulated water. When water enters the water sensor cartridge  62  through openings  65  the water-soluble element  75  dissolves, allowing springs  70  and  71  to expand and move plunger  72  to the right, pulling clamp  73  and wire  48  with it. Surfaces  76  and  77  stop the rightward movement of plunger  72  to limit the movement of wire  48 . The other end of wire  48 , being connected to the vertical extension  47  of latch  43  in FIG. 9, will pull the latch  43  as shown in FIG.  9  and thus close the valve to stop additional water leakage. Cable tubing  16  encloses wire  48  and provides the necessary axially rigid but flexible connection between the water sensor  17  and the valve  13 . As previously mentioned, this initiates the valve closure action and water flow through the valve  13  will cease. After water flow has stopped it is necessary to first find and repair the source of the water leakage, along with drying the area of leakage. Next, the expended sensor cartridge  62  with the dissolved water soluble element is removed and another cartridge, either new or used, containing a new water soluble element  75  is snapped in place. Then the valve  14  or  19 , referring to FIG.  1  through FIG. 4, is turned off to relieve water pressure on the shutoff valve  13  or  23  respectively. In order to reset the valve to its open position the portion of the valve housing that had moved to the right during valve closure, namely,  33 ,  38  and  39  along with the connected appliance hose must be manually pressed in an axial direction toward the water source in order to compress spring  42  to its minimum length. It can be seen that a position of pin  44  will be reached such that spring  52  in FIG. 9 can once again pull the latch  43  back into a locked position. The valve  13  is now in a re-latched, open state and water flow can be reestablished by opening the appropriate valve  14  or  19 . 
     One of the primary, advantages of the described invention relative to the prior art is the ease with which it can be installed without disrupting the existing water supply lines or the water connections to the applicable appliances. When installing the described shutoff valve and sensor to the water sources for a clothes washing machine, the first step is to turn off the faucets or valves  14  and  14 A controlling the hot and cold water to the clothes washing machine. Next, the washing machine hoses  18  and  18 A are disconnected from the hot and cold water faucets or valves  14  and  14 A. One described shutoff valve  13  is now threaded onto the hot water faucet and another shutoff valve  13 A is threaded onto the cold water faucet. Then the previously removed washing machine hoses  18  and  18 A are threaded onto the threaded outlets  33  of the hot and cold shutoff valves  13  and  13 A respectively. The sensor assemblies  17  and  17 A are now be placed on the floor adjacent to the washing machine or in a location that optimizes the possibility of detecting any water leakage. Once the water source faucets or valves  14  and  14 A are opened to allow flow to the washing machine the installation is complete. 
     In summary, the foregoing disclosure describes a latched, spring-loaded valve that, in conjunction with a water sensor and an activation mechanism, provides a means to turn off a water supply when a water leak is detected. This disclosure focuses primarily on specific applications such as clothes washing machines, dishwashing machines, toilets, sinks, and refrigerators equipped with ice cube makers, but could apply to appropriate, non-water, fluid-handling applications. Because of its design the present valve system requires no electrical power to function. It should be understood, however, that anyone skilled in the art might provide a switching means to detect when the valve has been shut off, and utilize the switching means to activate an audible or visual alarm. Likewise, the water sensor and associated activation cable could be replaced by an electrical solenoid, controlled by a separate electronic water sensing and control system. In addition, it should be understood that the above valve description should not preclude the incorporation of the valve shutoff system as an integral part of the manual shut off valves which have been designated by items  14 ,  14   a , and  19  in FIGS. 1 through 4. Although a particular type of valve has been used in the description of this invention, it should be understood that other types of valves that do not require axial elongation, such as ball valves, gate valves, check valves or the like, could be used without departing from the spirit of this invention, The description of this invention is illustrative and not limiting; further modifications will be apparent to one skilled in the art, in the light of this disclosure and the appended claims.