| 摘要 |
<p>1,103,835. Float valves. ENGLISH ELECTRIC CO. Ltd. 9 June, 1966 [10 June, 1965], No. 24630/65. Heading F2V. A float valve wherein the effective weight of the float is at its greatest at the beginning of the opening movement and the effective buoyancy is greatest at the beginning of the closing movement. The valve comprises a flexible valve member 13 and a float 14 including a hollow chamber 22 having an air vent 23 situated above the level of a fluid passage 24, a second sealed chamber 21 may also be provided. The cross-sectional area of the opening 24 is such as to permit fluid to pass in and out of the chamber at a rate lower than the rate of rise and fall of fluid in the vessel 10. The flexible valve member 13 is fixed at one end to the vessel 10 and has at its other end a latch bar 16 projecting through a slot 17 in a rigid float arm 18. As the level of fluid in the vessel rises the float arm 18 bears against a seating 15 and holds the flap 13 against the opening of a breather or fluid inlet pipe 12. If the fluid level falls the combined weight of the float and of the fluid in chamber 22 rotates the float clockwise until it rests against a stop 26. Meanwhile the fluid drains out of the chamber 22 at a predetermined rate. If the density of the fluid in which the float is immersed changes sufficiently, e.g. by raising its temperature the valve will open and cold fluid may be admitted in order to regulate the temperature of the fluid. The valve finds particular application in the headers of heat exchange elements or in the coolers of dry cooling tower installations.</p> |
