| 摘要 |
A flow control means comprising a flow sensing means (18), a valve means (15), actuating means (16) to move said valve means between an open and a closed condition, and a control means (17) to cause said actuating means to move said valve means between said open and closed conditions, in accordance with a predetermined flow of said fluid. The flow sensing means may comprise at least one of: a) means to move said valve means to said closed condition to interrupt the flow of fluid therethrough after uninterrupted flow of fluid past said flow sensing means for a predetermined period, b) means to move said valve means to said closed condition to interrupt flow of fluid therethrough upon intermittent flow of fluid past said sensing means. The flow sensing means may comprise at least one of: a) a first flow sensing means (18a) adapted to sense a relatively high flow rate and wherein said control means (17) causes said actuating means (16) to move said valve means to said closed condition to interrupt said flow of fluid therethrough after said uninterrupted flow of fluid past said first flow sensing means for said predetermined time period, and/or upon said intermittent flow of fluid past said first flow sensing means, b) a second flow sensing means (18b) adapted to sense a relatively low flow rate and wherein said control means (17) is adapted to cause said actuating means (16) to move said valve means to said closed condition to interrupt flow of fluid therethrough upon said intermittent flow of fluid past said second flow sensing means and/or after uninterrupted flow of fluid past said second flow sensing means for a predetermined time period. |
