Magnetic valve stops flood before it happens

Tom Shelley reports on a magnetically actuated valve system with great potential to prevent serious problems A magnetically actuated shut off valve system has been developed to prevent sinks and baths overflowing but also has many other potential uses. While we reported on the original version of James Barnham's "Nova-Flo" idea in Eureka's August 2004 edition, the new version, poised to go commercial, achieves the same goal but by a totally different method, and one which is distinctly transferable to other purposes. In the new system, water flowing through the overflow at more than a trickle causes a float to rise in a chamber, because of a restriction downstream from the entrance to the float chamber. A magnet is attached to the float on a stalk. In its normal, lowered position, the lower pole of the magnet attracts the opposite poles on two valve flaps in the flow lines to the taps. When the float rises, this places the other pole of the magnet on the stalk, of the same type as those on the valve flaps, between them, so as to oppose them and push them apart. Water pressure in the flow lines presses the valve flaps against their seats, shutting off the water flow. Resetting is by turning off the taps. With equal pressure above and below the flaps, these fall back into their initial positions, assisted by the magnet on the stalk, which through the emptying of the float chamber, is back in its initial position. A new version suitable for commercial production has been designed using SolidWorks. The Nova-Flo invention has been patented, and turned into a proper business with an office in the South Bank Techno Park, assisted by a £6,000 grant from the Emerald Fund. The idea has received a Designer Award from the Institution of Engineering Designers and is to be exhibited in the form of a working system attached to the front section of a bath at the Ideal Home exhibition to be held at Earls Court from October 7th to 16th in October 2005. The stand number is to be R25. Mr Barnham is currently looking for licensees for his invention which he has just redesigned using SolidWorks. The latest commercial design is more compact than might be expected from looking at the diagram, but the principle is the same. The development has already aroused considerable interest in those responsible for housing trusts, especially those required to provide accommodation to the elderly, as well as those responsible for public facilities prone to the attention of vandals who take mindless pleasure in causing damage and disaster. The same principles could equally well be applied to preventing overflowing in process plant vessels and other industrial and commercial applications. Oil hydraulic valve applications are also possible. Nova-Flow James Barnham at Nova-Flo Pointers * System is activated by excessive flow flooding a float chamber so as to lift a magnet on a stalk * As one pole of the magnet on the stalk is replaced by the other, two flap valves that were formerly attracted towards the stalk are instead pushed apart. Flow to the taps then presses these against seats, shutting off the flow * Resetting is by turning off the taps