Fluid shut off valve and fill level indication

A valve to monitor the level of fluid in a storage tank while the tank is being filled, cutoff the flow of fluid when the tank is in a full condition, and as long as the filling pressure is on the valve the valve will remain cutoff even if the fluid level in the tank has lowered comprising in combination:

• a lower cap threadably received to a filling neck of said storage tank;
• an upper filling tube coaxially received through said lower cap and threadably received in fluid entrance end of an upper outer valve body;
• a lower outer valve body that threadably receives said upper outer valve body;
• a lower filling tube secured by a retainer threadably received in the fluid exit end of said lower outer valve body;
• an upper and lower inner housing coaxially received and having an engagement therebetween at a mating surface in said upper and lower outer valve bodies;
• said upper inner housings with a first bore offset from a second bore in said lower inner housing;
• a first and second valve seat resultant of the exposed area of said offset bores at said mating surface;
• said first valve seat exposed to said fluid entrance of said valve;
• said second valve seat exposed to said fluid exit of said valve;
• a butterfly valve centerline perpendicular to said offset bores and radially intersecting said mating surface;
• said butterfly valve with a first and second semicircular member with offset axes;
• said semicircular members offset axes and radii are matched to said offset bores;
• said semicircular members axes are perpendicular to said butterfly valve centerline;
• a shaft coaxially received through said butterfly valve centerline;
• a first flow cutoff surface of said first semicircular member is disposed on a plane intersecting and parallel to said butterfly valve centerline extending radially from said shaft and faces said first valve seat;
• said second semicircular member is diametrically opposite said first semicircular member, wherein, a second flow cutoff surface of said second semicircular member faces said second valve seat;
• said shaft is rotatably received for moving said butterfly valve from an open position to a closed position;
• said first and second flow cutoff surfaces contact said first and second valve seats in said closed position;
• the area exposed to said first bore of said first semicircular member is greater than the area exposed to said first bore of said second semicircular member;
• said first semicircular member is held in contact with said first valve seat and said second semicircular member is held in contact with said second valve seat by the product of the greater differential area of said first semicircular member and the filling pressure and will remain in said closed position until said filling pressure is reduced;
• when said butterfly valve is in any position from said open position prior to said closed position the area between said first valve seat and said butterfly valve is equal to the area between said second valve seat and said butterfly valve, and the flow through said areas are substantially equal;
• said first semicircular member operates in said first bore;
• a relief valve is spring biased to an open position;
• said relief valve is disposed in said first semicircular member;
• said relief valve is adjustable for different fluids by changing the pressure of said spring;
• an arm fastened to said shaft;
• a linkage fastened to said arm;
• a float coaxially slidably received over said upper filling tube and fastened to said linkage;
• said float contacts and follows said level of said fluid in the filling process to rotate said butterfly valve from said open position to said closed position;
• and
• after said filling pressure is off and said fluid lowers, said float follows said fluid level until said butterfly valve is in said open position.