| 摘要 |
PROBLEM TO BE SOLVED: To provide a check valve with a built-in back pressure valve, achieving reliable operation with minimized components. SOLUTION: A casing 10 is provided with a primary side passage 11 and a secondary side passage 12, and a check valve element 20 is arranged between these passages. A first spring 24 is provided between the valve element 20 and a first stopper member 23 in the secondary side passage for thrusting the valve element 20 to the primary side passage. On the other hand, a back pressure valve element 30 is built in the check valve element 20, which is closed when pressure in the primary side passage is high and opened when pressure in the secondary side passage is high. The check valve element 20 is opened when liquid is supplied, and the back pressure valve element 30 is opened when pressure in the secondary side passage rises. No need therefore exists for extra piping, which greatly contribute to reduce the size of a filling device. Machining accuracy is improved for the casing of the check valve and easy maintenance and inspection are allowed, and a manufacturing cost is reduced. Furthermore, the stronger and smaller back pressure valve results in the compact check valve. COPYRIGHT: (C)2004,JPO&NCIPI
|
