Abstract:
Embodiments are provided for an automatic fluid shut off device having a float disposed in a fluid catch basin attached to a first end of a rod movable in a direction of rising fluid in the catch basin; a second rod end extending to a fluid supply base and terminating adjacent to a restrained latch arm end, the latch arm end configured to be pivotably displaceable upon a force by the second rod end in response to a rising fluid in the catch basin; the latch arm pivotably connected to a shut-off valve; and the shut off valve retained in an open position while the latch arm is restrained, and under a rotational force to close the shut-off valve upon a release of the latch arm in response to the force by the second rod end. The latch arm can be restrained by a latch arm retention notch extending downward and inward.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. national phase application of International Application No. PCT/US2012/061112, filed Oct. 19, 2012, which claims benefit of U.S. Provisional Application 61/549,842, filed Oct. 21, 2011, which are hereby incorporated herein by reference in their entirety. 
    
    
     FIELD 
     The embodiments described herein provide fluid shut-off devices and methods, and specifically fluid shut-off devices and methods using mechanical action of a float to activate a spring loaded shut-off valve. 
     BACKGROUND 
     Water damage from leaking water reservoirs, such as hot water tanks, dishwashers, and the like, cause damage to many homes each year. Some devices and methods in the art have been developed to attempt detection and shut-off of water leaks from such reservoirs. These devices are typically complicated, expensive and often require the use electrically powered means to shut off the water supply if a leak is detected. One such system is sold under the trade name FLO-LOGIC of Raleigh, N.C., is dependant on electric power. These types of devices could potentially provide no protection if the electronic means fails or electrical power is interrupted. 
     Other attempts to provide automatic fluid shut-off capability can include a dissolving component, such as one sold under the trade name WAGS valve by Taco, Inc. of Cranston, R.I. Again, this type of system is complicated, expensive and requires the plumbing be run at floor level. Other complicated, space consuming, inefficient, and cost-ineffective attempts are also known (See generally, U.S. Pat. Nos. 7,665,482, 6,253,785and 2,724,401). 
     Accordingly, the known processes to shut off a water supply from a leaking water reservoir provide significant advances in the art, but further advances are possible and desired. 
     SUMMARY 
     The embodiments described below provide mechanical fluid shut-off devices and methods, and specifically fluid shut-off devices and methods using a mechanical action of a float to activate a spring loaded shut-off valve. 
     In one embodiment, an automatic fluid shut off device is provided having a float disposed in a fluid catch basin attached to a first end of a rod movable in a direction of rising fluid in the catch basin; a second rod end extending to a fluid supply base and terminating adjacent to a restrained latch arm end, the latch arm end configured to be pivotably displaceable upon a force by the second rod end in response to a rising fluid in the catch basin; the latch arm pivotably connected to a shut-off valve; and the shut off valve retained in an open position while the latch arm is restrained, and under a rotational force to close the shut-off valve upon a release of the latch arm in response to the force by the second rod end. The latch arm can be restrained by a latch arm retention notch extending downward and inward at about a 3.5 degree angle. 
     In some embodiments, an overall buoyancy force of the float can be, for example, up to about 1.5 pounds (about 680 gms) against the latch arm and the rotational force against the shut-off valve is at least about 18 pounds (about 8200 gms). 
     In some embodiments, the rotation force can be supplied by a torsion spring. The torsion spring can have first and second ends generally in parallel and wherein the first torsion spring can be connected to a handled rotatably attached to the shut-off valve and the second torsion spring end is attached to the base. The torsion spring can be formed from music wire with a diameter of about 0.105 inches (about 2-3 mms). 
     In some embodiments, the shut-off valve can be a ¾″ (about 19 mms), four bolt, quarter-turn ball valve. The base and latch arm can be formed from a variety of materials such as an acetal polymer. 
     In some embodiments, the catch basin can be disposed under a water heater and configured to displace the latch arm to a point of release in response to about 1 to 2 inches of water (about 25-50 mms) in the catch basin. 
     The current embodiments also provide a method to shut off a water supply, which can have the steps of: providing a first force in response to unanticipated presence of a fluid; displacing a restrained latch arm connected to a shut-off valve handle past a stop in response to the first force; rotating the shut-off valve connected to a fluid supply by a second force in response to a latch arm displacement beyond a release point. It is noted that the term force as used herein describes the overall weight equivalent of effort acting on the specific element described. 
     In some methods, the restrained latch arm can be restrained by the second force. In some embodiments, the first force can be provided by a buoyancy force and the second force is provided by a coil spring. The first force can be, for example, up to about 1.5 pounds (about 680 gms) and the second for is at least 18 pounds (about 8200 gms). 
     Other features will become more apparent to persons having ordinary skill in the art to which pertains from the following description and claims. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The foregoing features, as well as other features, will become apparent with reference to the description and figures below, in which like numerals represent elements, and in which: 
         FIG. 1  is side view of an embodiment of the present devices configured for use with a water heater; 
         FIG. 2  is a sectional view of an embodiment of the present devices taken along section lines II-II in  FIG. 1 ; 
         FIG. 3  is a sectional view of an embodiment of the present devices taken along section lines II-II in  FIG. 1  upon activation by the float; 
         FIG. 4  is a top view of an embodiment of the present devices; 
         FIG. 5  is a side view of an embodiment of the present devices; 
         FIG. 6  is a detail view of Area VI indicated in  FIG. 2 ; 
         FIG. 7  is an alternate embodiment of the present devices configured for use with a water heater; 
         FIG. 8  is an alternate embodiment of the present device latch arm and base notch; and 
         FIG. 9  is a perspective view of an embodiment of the present devices. 
     
    
    
     DETAILED DESCRIPTION 
     The embodiments described below provide mechanical and non-electrical fluid shut-off devices and methods, and specifically fluid shut-off devices and methods using a mechanical action of a float to activate a spring loaded shut-off valve (such as a spring loaded quarter-turn ball valve). In some cases the embodiments can be actuated upon a failure of a fluid reservoir. While the present embodiments are described for a catch basin disposed under a water heater, it is noted that other configurations can be considered within the scope of the presented embodiments. Such configurations could also include any applications involving water supplies and other fluids and gases supplied under pressure, and appliances such as ice-maker water supplies, dishwashers, clothes washers, gas lines, irrigation systems, and the like. 
     An advantage of the present embodiments is to provide a solely mechanical actuatable shut off valve upon detection of an irregular flow of the fluid or gas. In one instance an event such as raising a rod attached to a float urging an end of a spring loaded paw/latch arm past its retention point to force rotation of a ball valve to shut off the fluid supply. Such a device is not dependant on electrical power supply for actuation. 
     In one embodiment, the device can shut off the flow of liquid from a float disposed in a catch basin. In use, as unanticipated fluid accumulates in the catch basin, the float rises with the accumulated liquid. As the float rises it can lift a pivoting lever arm acting as a fulcrum. A rod connected at some point along the lever arm lifts with the float and lever arm to apply a force against a latch arm end attached to a handle of a spring loaded valve. As the end of the latch arm rises with the rod, it reaches a release point, allowing a torsion spring to force a valve handle to a closed valve position, thus stopping the flow of any liquid or gas from the supply. 
     Accordingly, for illustrative purposes only, described herein is one embodiment of the present device configured for use as a shut-off valve for the water supply to a water heater. Turning now to the figures, there is shown an automatic fluid shut-off device generally indicated at  20  ( FIG. 1 ). As shown, a fluid  28  is fed to a fluid reservoir, such as a water heater  22 , by a fluid/water supply  26 . Surrounding the bottom of water heater  22  a catch basin  24  can be provided to receive fluid, such as upon failure of the fluid reservoir  22 . In one embodiment, such as shown in  FIG. 7 , catch basin  24  can have a depth in the range of up to the height of the reservoir, but preferably about 2.5 (about 64 mms) to 3.5 inches (about 89 mms), though many variations are possible within the scope of the present embodiments. Catch basin  24  can have a variety of shapes and sizes and made from a variety of materials such as plastics, ceramics, glass, masonry, and the like. In some embodiments catch basin  24  can even be a perimeter damn formed around the fluid reservoir. The size of the catch basin should be limited to allow for a minimal ‘footprint’ on the floor where water heater  22  is located. For example, in one embodiment, catch basin  24  can have an interior diameter about 4 inches (about 100 mms) greater than the outer diameter of the water heater. In this example, catch basin  24  would have a clearance of a minimum of two inches (about 50 mms) outside of the perimeter of water heater  22 . 
     As shown in  FIGS. 1 and 7 , a fulcrum arm  32  is pivotally hinged to a base  34  at pivot  37 . For illustrative purposes only, in one embodiment base  34  can stand at about 4.4 (about 112 mms) inches in height. Base  34  can be formed from a variety of rigid materials to provide stability to the lever action of the float and can be fixed to the floor or within the catch basin ( FIG. 1 ), attached to the wall of the catch basin (not shown), or outside of the catch basin ( FIG. 7 . Again, for illustrative purposes, the length of fulcrum arm  32  can be about 5.5 (about 140 mms) inches. In this embodiment, at about ¾″ (about 19 mms) from the axis point  37  of fulcrum arm  32  to base  34 , a pivot point  35 , such as a hinged clevis, is attached. At the distal end of the fulcrum a float  30  is attached. Float  30  can be formed from a variety of materials configured to be buoyant relative to the fluid  28 . For example, where fluid  28  is water, the float can be made from cork, wood, closed cell foams (such as a closed cell extruded polystyrene foam sold under the trade name STYROFOAM), and the like. In embodiments using a closed cell STYROFOAM, float  30  can have a volume of about 16.5 square inches (420 sq mms) and/or measure about 1.5″ (38 mms) wide, about 5.5″ (140 mms) long, and about 2″ (51 mms) high. In any event, the float should be able to generate approximately at least about one (1) pound (about 450 gms) of lift force (buoyancy) when submerged in the fluid/water. 
     As the more lift is applied to float  30  at the end of fulcrum arm  32 , pivot point on fulcrum arm to rod  36  can be configured to be at a point where the transferred force provides about six pounds (about 2700 gms) of lift. Accordingly, at point  35 , a rod  36  is disposed along the length of the fulcrum arm  32  so that 6 pounds (about 2700 gms) of lift can thus be applied to rod  36 . In other words, rod  36  is positioned at a point of the fulcrum arm such that 6 times the buoyant force of the float is applied. In another example, rod  36  can be positioned on fulcrum arm such that the force ultimately applied to a latch arm (see below) can be, for example, up to about 1.5 pounds (about 680 gms). Ultimately, the force applied would be sufficient to release the latch arm. This desired force would need to consider several factors such as the friction of all the components, the weight of the components (e.g., the weight of rod  36 ), the potentially predicted buildup of dust/debris that may occur among the components over time, and the like. 
     Attached to the clevis is a rod  36 . Rod  36  can be any rigid rod that can transfer the buoyant force of the float to the shut-off assembly as described below. Rod diameter, length, weight, density, desired rigidity and cost can be configured for specific applications. For example, rods can be formed from stainless steel, carbon fiber, wood, plastics, other types of steel (such as a typical number 8 threaded metal rod) can be used. Rod  36  extends from the clevis  35  toward a shut off valve assemble  38 . Positioning, securing and protecting rod  36  can be achieved by sleeves and guides along its length (not shown). 
     Shut-off valve assembly  50  can include a shut off valve such as a handle activated ¾″ (about 19 mms), four bolt, quarter-turn ball valve. While the shut-off valve is described for a quarter-turn ball valve, it is noted that other types of shut-off valves could also be within the scope of the present embodiments. Exemplary shut-off valves could also include: butterfly valves, gate valves, piston valves, and the like. 
     The actuation assembly  38  components, as shown, can be bolted onto valve  50 . Assembly  38  can provide a valve assembly shut-off base  40  that has a guide (as shown a valve assembly rod guide with a rod arm bore  44 ) for rod  36  to travel freely through and to guide rod  36  to a latch arm  42 . An area of base  40  can have a notch cutout  45  at the guide hole. Base  40  and latch arm  42  can be formed of a variety of materials including metals and plastics. For example, plastic embodiments can include acetal polymer materials, such as one sold under the trade name DELRIN. As shown, base  40  is ‘upstream’ in the fluid supply of shut off valve  50 . It is noted though that the present embodiments can be practiced so the base  40  can be on either side of shut off valve  50 . 
     As shown in  FIG. 3 , as rod  36  rises, such as in response to a rising float in a catch basin, rod  36  end applies the rising force against an end of latch arm  42 . As latch arm  42  is displaced upward, it rotates about a latch arm axis point  48  that is connected to the end of a handle  66 , which as shown is rotatable against an axis perpendicular to the pivot of latch arm  42 . Handle  66  turning about its axis cause valve  50  to rotate to an open or closed position. When latch arm  42  is held in place by shut-off base notch  45 , valve  50  is maintained in an open position to allow flow of fluid through the water supply  26 . 
     As latch arm is displaced and extends beyond shut-off base notch  45 , handle  66  is under a rotational force to close by a torsion spring  56  mounted, in this illustration above valve  50 . It is noted though that some embodiments can be configured to employ a coil spring, though a torsion spring is preferred as it allows for a more efficient, cost effective and compact design. The ends  58  and  60  of torsion spring  56  are preferably in a generally parallel orientation held in place by raised stops  64  and  62  respectively on handle  66  and a rod anchored by the base  40 . The torsion spring  56  can be formed from a variety of materials such as music wire with a diameter of 0.105 inches, and free position of ends turning radius of 360 degrees. Torsion spring  56  can be wound about a spool, for example, a 1 and ⅜″ spool (i.e., about 35 mms). In any event, torsion spring must be able to provide enough force to rotate valve  50  in the presence of the fluid under pressure. For most embodiments, torsion spring  56  should be able to generate at least 18 pounds (about 8164 gms) of force. In one embodiment, torsion spring  56  can generate about 21 lbs (about 9500 gms) of force. 
     Returning to the latch arm, as described above, disposed at the end of handle  66  a pivotable (at  48 ) latch arm  42 . Latch arm  42 , as shown, is “L” shaped and rests in cutout notch  45  in base  40  as shown in  FIG. 6 . Again, cutout notch  45  and the ‘L’ shaped latch arm  42  are made from a material that is strong enough to hold the full force of the spring tension and have a low coefficient of friction to allow latch arm to be displaced upward under the rising force of rod  36 . Latch arm  42  and notch  45  are also configured by their angular orientation to retain the latch arm  42  at the bottom of notch  42 . 
     As shown most clearly in  FIG. 6 , latch arm  42  can be held in place under the force of the torsion spring in the direction shown at  68 . Latch arm  42  can optionally have an angle  54  (such as a 5.5 degree angle). An angle  52  (such as about a 3.5 degree angle) can also be optionally formed on side wall  70  contact surface of cutout notch  45  on base  40  to drive the latch arm apex point  46  in and down along the side wall  70  until it reaches a point where it can be positioned approximately adjacent to the end of rod  36  to allow engagement as rod  36  raises. With the force at these contact surfaces, the angles provide a desired downward pull configuration on the latch arm to prevent its inadvertent release. Given the pre-configured angles and coefficient of friction, the force needed to move the latch arm  42  above side wall  70  can be calculated with predictability. Further angle  54  can be configured to provide clearance as it traverses upward along side wall  70 . 
     An alternate latch arm retention configuration is illustrated in  FIG. 8 . As shown, latch arm  42   i  edge  76  is held against base  40   i  on its side wall  74 . Edge  76  and sidewall  74  are generally parallel and at right angles to latch arm lower edge  80  and base top  78  respectively. The right angles allow ease of manufacturing, such as for injected molded plastic components. It is noted that the end portion of the “L” of latch arm  42   i  is configured to be a length  72  to allow a preconfigured force (such as at least 1.5 pounds of force) to overcome the friction between surfaces  74  and  76  and allow the latch arm to swing upward from the force generated by the raising of rod  36 . 
     Accordingly, in use, as fluid reservoir  24  fills with fluid  28 , float  30  is lifted. Float  30  raises the end of lever arm  32  acting as a fulcrum lifting rod  36 . As rod  36  raises, it applies force to end of latch arm  42  to overcome the down and inward force of the torsion spring  56  provided by angles  54  and  52 . Upon the latch arm end reaching the top edge of side wall  70 , the full force of torsion spring  56  is released to rotate valve handle  66  from an open position to the closed position. 
     A clear advantage of the current device is that it is totally mechanical. The device can also be custom fitted to any size water heater without major re-routing of plumbing. It can be configured to trigger with a water lever of about 0.5-2 inches (about 12 to 50 mms) within the catch basin. Optimally the device is made from materials that resist corrosion and wear such as material sold under the trade name of DELRIN. 
     While the products and methods have been described in conjunction with specific embodiments, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description.