Abstract:
A water supply shutoff valve system is used with a fluid storage tank, such as a hot water heater, to automatically shut off the water supply to the storage tank as a result of leak containment which in turn causes a magnetic float to rise and consequently produce the mechanical force necessary to release and close a spring loaded water supply valve.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not applicable. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     BACKGROUND—FIELD OF THE INVENTION 
     This invention relates to a fluid supply shut-off valve system used to shut off the supply of fluid to a hot water heater when a leak or rupture is detected. 
     BACKGROUND—DESCRIPTION OF PRIOR ART 
     Hot water heaters are well known for the property damage that can result from an unattended leak or rupture. To minimize the damage resulting from leakage, numerous designs have been created for fluid supply shut-off valve systems. These designs involve different types of shut-off valves that close when activated or actuated by various means of leak detection. Prior art U.S. Pat. No. 4,909,274 is one such design. That design operates by containing the leaking fluid which raises a float and rod assembly and causes a set of gears to close a valve thus shutting off the supply of water to the water heater. That particular design requires no electrical power but is not economical to manufacture and is also impractical to install and operate. 
     Prior art U.S. Pat. No. 6,021,808 uses pressure differential that occurs during a rupture to close a shut-off valve. That design is not economical to manufacture, requires maintenance due to its daily moving parts, and may not work under a drip-type leak scenario. 
     Still, several other prior arts such as U.S. Pat. Nos. 3,770,002, 4,805,662, 5,008,650, 5,632,302, 5,992,443, and 6,024,116 use various means of leak detection to cause an electrically operated shut-off valve to close. These designs are also uneconomical and require electrical power in order to operate. Accordingly a need exists for a device to shut off the supply of water to a water heater during a leak or rupture that is economical to manufacture and install, simple and reliable to operate, requires minimum maintenance, and requires no electrical power. The invention disclosed herewith accomplishes said criteria 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention involves the collection of water resulting from a leak or rupture at a water heater or the like. The leaking water is collected in a leak collection pan that is located beneath a water heater. A float containing a permanent magnet is located in the leak collection pan. Upon reaching a predetermined water level in the leak collection pan, the magnetic float and a rigidly attached vertical float rod rise and slowly enter the magnetic field developing between the top of the magnetic float and both the bottom of the water heater as well as a magnetic attractive float stop. The stationary float stop is located adjacent to the outside bottom jacket of the water heater. The magnetic float and its float rod are accelerated quickly upward due to the magnetic force. The top end of the float rod strikes the bottom end of a vertical lift rod with a predetermined force. Upon said impact of force the lift rod is quickly forced upward and causes the release and closing of a spring loaded quarter-turn ball valve. The closure of the ball valve shuts off the supply of water to the water heater. A check valve in the outgoing hot water heater line then automatically closes due to a no flow condition and prevents any back flow drainage. 
     The resulting property damage is minimized due to the automatic shut off of the water supply to the water heater and the check valve&#39;s prevention of any back flow drainage. 
     Several objects and advantages exist with the present invention. One such advantage of our invention is that there are no personnel safety hazard concerns regarding electrical shock with water contact as this invention requires no electrical power in order to operate. Another advantage over the prior art is that the present invention performs even during a power outage. 
     This invention is constructed of simple materials and hardware that can be found in a typical hardware store. No newly designed or newly manufactured valve or other major component is required. Standard “off the shelf ” hardware, valves, and magnet are used in the construction of this invention. Hence, minimal initial capital is required for tooling and production. 
     The simplicity of this invention is clearly an advantage over prior art such that a typical home owner could easily understand, purchase, install, and operate this invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the present invention as would be typically installed on a water heater in the normal operating position. 
     FIG. 2 is a cross-sectional view of the present invention depicting the float, magnet, float rod and lift rod assembly in the normal operating position. 
     FIG. 3 is a perspective detail of the valve lever arm assembly, according to the present invention, showing the incoming water supply ball valve lever arm in the normal operating spring-loaded position that is maintained by the hooked end of the lift rod. 
     REFERENCE NUMERALS IN DRAWINGS 
       20  water heater 
       22  leak collection pan 
       24  ball valve 
       25  water supply line 
       26  check valve 
       27  outgoing hot water line 
       28  spring 
       30  spring wheel 
       31  capped riser pipe 
       32  valve lever arm 
       34  lift rod 
       36  lift rod housing 
       38  magnetic float 
       38   a  top float piece 
       38   b  bottom float piece 
       40  float stop 
       42  housing clamp 
       44   a  coupling;  44   b  coupling 
       46  end connector 
       48   a  magnet casing 
       48   b  permanent magnet 
       50  float rod 
       52  required rod gap 
       54  nut 
       56  tee nut 
       58  nut 
       60  tee nut/guide 
       62  lever bolt 
       64   a  nut;  64   b  nut;  64   c  nut,  64   d  nut 
       66   a  washer;  66   b  washer 
       68  roller/spacer 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows a typical water heater  20  located above a leak collection pan  22 . A quarter-turn ball valve  24  is shown installed in an incoming water supply line  25 . The ball valve is shown in the normally open position. A check valve  26  is shown installed in an outgoing hot water fine  27 . Check valve  26  is shown in the normally open position as water passes through ball valve  24 , into water heater  20 , and comes out as hot water through outgoing hot water line  27 . 
     An adjustable spring wheel  30 , such as a pulley, maintains tension on spring  28  whose opposite end is attached to a valve lever arm  32 . A hooked end of a lift rod  34  keeps lever arm  32  from turning 90 degrees and closing ball valve  24  against the predetermined set tension of spring  28 . 
     Lift rod  34  is vertically guided in a tubular lift rod housing  36 , such as an electrical conduit. Lift rod  34  is guided using washer-containing conduit couplings  44   a  and  44   b,  and a tee nut/guide  60 . Lift rod housing  36  is attached to the outside jacket of the water heater using a plurality of housing clamps  42 , such as conduit clamps. Lift rod housing  36  is assembled using a magnetically attractive float stop  40  on its bottom end, such as a partial iron floor flange, and an end connector  46  on its top end. Coupling  44 a and coupling  44   b  are also used to adjust the overall length and placement of lift rod housing  36  during installation. 
     FIG. 1 also shows a magnetic float  38  in its normal operating position centered below lift rod housing  36  and resting on the inside bottom of leak collection pan  22 . Once sufficient leak water is collected in the leak collection pan  22 , magnetic float  38  will begin to rise upward toward the center of float stop  40 . 
     FIG. 2 is a cross-sectional view of a magnetic float  38 , a float rod  50 , and a lift rod  34 . A magnetic float  38 , such as a candy tin, is constructed of top float piece  38   a,  and of bottom float piece  38   b.  A shallow pot ceramic permanent magnet  48   b  is attached to its magnet casing  48   a.  Magnet casing  48   a  is attached to top float piece  38   a  using a nut  54  and a tee nut  56  on a threaded end of aluminum float rod  50 . 
     As the collected leak water rises, magnetic float  38  rises toward the bottom of the water heater and float stop  40 . Once the magnetic attraction between magnetic float  38  and the bottom of the water heater and float stop  40  is maximized, magnetic float  38  will quickly accelerate upward, displacing the required rod gap  52 , until it stops on simultaneous impact with the bottom of the water heater, float stop  40 , and lift rod  34 . A nut  58  helps transmit maximum impact force on the blunt end of lift rod  34 . 
     FIG. 3 shows ball valve lever arm  32  in the normal operating spring-loaded position. A spring  28  maintains predetermined constant tension on valve lever arm  32 . The end of lever arm  32  has a hole drilled through it in order to accommodate a lever bolt  62 . Lever bolt  62  is secured to valve lever arm  32  with a nut  64   c  and a nut  64   d.  One end of spring  28  is then hooked over the head shaft end of lever bolt  62 . The opposite end of lever bolt  62  is comprised of a cylindrical roller/spacer  68 . Said roller/spacer  68  is secured in place, but free to roll, by a washer  66   a  and a nut  64   a.  A washer  66   b  and a nut  64   b  are used on the opposite end of roller/spacer  68 . 
     The hook end of lift rod  34  is hooked over roller/spacer  68  and maintains spring  28  position and tension. Spring  28  is attached to spring wheel  30 , in FIG. 1, which can be turned either clockwise or counterclockwise in order to increase or decrease spring tension. Spring wheel  30  is attached to capped riser pipe  31  and can be adjusted to slide vertically up or down in order to accommodate the closing arc path of valve lever arm  32 . 
     When lift rod  34  receives the impact force from float rod  50 , in FIG. 2, lift rod  34  with the assistance of roller/spacer  68 , FIG. 3, travels upward and then frees valve lever arm  32  to yield to the tension of spring  28  thus closing ball valve  24 , FIG.  1 . Said closing of ball valve  24  shuts off the incoming water supply from water supply line  25 . 
     At this stage there is no flow entering the inlet nozzle of the water heater. Consequently there is no flow leaving the water heater through outgoing hot water line  27 . Under said condition check valve  26  automatically closes preventing any back flow drainage. 
     At this point there is no hot water service available until the system is repaired and spring  28 , valve lever arm  32 , lift rod  34 , float rod  50 , and magnetic float  38  are manually placed back into the normal operating position. 
     RAMIFICATIONS 
     The reader will see the simplicity, reliability and inexpensive cost associated with this invention as used at a water heater as shown in the drawings. However this invention is not limited to only water heater applications. This invention can be applied similarly at water storage tanks, washing machines, drinking fountains, or confined areas such as basements. 
     This particular water heater application uses a leak collection pan. Other applications would not necessarily require a pan. A shallow sump or a curbed area that would retain leakage sufficient to cause the required float lift would suffice. Example: A shallow sump or a curbed area could be used in a basement to collect leakage from leaking equipment or ruptured/frozen water lines eliminating the need of a leak collection pan. If the device was located in the low point of a basement, neither a leak collection pan, sump or a curbed area would be required. 
     The present invention can be used on existing hot water heater installations as well as new installations. Optionally a water heater manufacturer could incorporate this invention during equipment fabrication such that the device is built internally within the water heater jacket, or fabricated as such to easily accept the later addition of the device. This invention could be supplied as part of the water heater equipment proper or as an add-on assembly kit. 
     A removable protective housing could be attached to shield the magnetic float from incidental contact with foreign objects that might otherwise cause the float to operate improperly. Ramifications include safely directing a water heater&#39;s temperature and pressure relief valve discharge line into the leak collection pan. This discharge would cause the required float movement and consequent bad valve closure. Although there might not be an actual water leak, this ball valve closure indicates to the owner that there might be a serious water heater operating malfunction and potential safety hazard.