| 主权项 |
1. A flow-control passive valve (32) for controlling flow of a fluid between an upstream space (22) at high pressure (pH) and a downstream space (28) at low pressure (pL), the flow-control passive valve (32) comprising:
a valve body (34, 36) in fluid communication on one side (64) with the upstream space (22) and on another side (82) with the downstream space (28), a first space (62) and a second space (66) being defined within the valve body (34, 36); a movable member (48) slidably received in a chamber (46) of the valve body (34, 36); resiliency (54) applying on the movable member (48) a force tending to keep the movable member in a given “non-working” position; and metering discs (56, 64, 68, 72, 76) for metering the flow of the fluid from the upstream space (22) to the downstream space (28) through the valve body (34, 36), the metering discs (56, 64, 68, 72, 76) including:
a first fixed restrictor (64) through which the first space (62) is in fluid communication with the upstream space (22);a second fixed restrictor (76) through which the first space (62) is in fluid communication with the downstream space (28); a first variable restrictor (56, 72) a restriction amount of which depends on a position of the movable member (48) and through which the first space (62) is in fluid communication with the downstream space (28) in substantial parallel to the second fixed restrictor (76);
a second variable restrictor (56, 68) a restriction amount of which depends on the position of the movable member (48) and through which the first space (62) is in fluid communication with the second space (66);a third fixed restrictor (56, 40) through which the second space (66) is in fluid communication with the downstream space (28), wherein a pressure (p1) in the first space (62) is lower than a pressure in the upstream space (22) as a result of a pressure drop through the first fixed restrictor (64) while a pressure (p2) in the second space (66) is variable between the pressure (p1) in the first space (62) and the pressure (pL) in the downstream space (28) depending on the position of the movable member (48); wherein the valve body (34, 36) includes a bottom wall (38) having an opening (64) defining the first fixed restrictor (64), a top wall (42) having an opening (82) for connection with the downstream space (28), and a substantially cylindrical lateral wall (40); the chamber (46) of the valve body (34, 36) is a substantially cylindrical chamber defined by the bottom wall (38), by the top wall (42), and by the cylindrical lateral wall (40); the movable member (48) is slidable along a direction of an axis of the chamber (46) of the valve body (34, 36) and includes a bottom wall (50) facing the bottom wall (38) of the valve body (34, 36) and a substantially cylindrical lateral wall (52); the movable member (48) has a center hole (78) through which the chamber (46) is in fluid communication with the first space (62) via the second fixed restrictor (76) and the first variable restrictor (56, 72) as well as at least one opening (80) through which the chamber (46) is in fluid communication with the second space (66) via the third fixed restrictor (56, 40); the resiliency (54) applies on the movable member (48) the force tending to urge the bottom wall (50) of the movable member against the bottom wall (38) of the valve body (34, 36); the metering discs (56, 64, 68, 72, 76) further include at least one disc (56) that is substantially axially interposed between the bottom wall (38) of the valve body (34, 36) and the bottom wall (50) of the movable member (48) and has a center hole (74) in fluid communication with the center hole (78) of the bottom wall (50) of the movable member (48); and the at least one disc defines the second fixed restrictor (76), the first variable restrictor (56, 72), the second variable restrictor (56, 68), and the third fixed restrictor (56, 40). |
