Patent ID: 9416889
Filing Date: 2016-08-16
CPC Classification: F16K,Y10T

Claim Text:
1. A fluid-driven shutoff valve including: a main body formed with an inlet passage and an outlet passage; a valve seat formed in the main body; a valve element movable into or out of contact with the valve seat; a drive part integrally connected to the valve element; and a pilot opening/closing valve configured to supply compressed fluid to drive the drive part, wherein the pilot opening/closing valve includes: (a) a first needle valve, a first motor configured to change an opening degree of the first needle valve, and a first check valve configured to allow the compressed fluid to flow only from a pilot opening/closing valve side to a drive part side, and (b) a second needle valve, a second motor configured to change an opening degree of the second needle valve, and a second check valve configured to allow the compressed fluid to flow only from the drive part side to the pilot opening/closing valve side, wherein each of the first and second needle valves includes a needle valve element and a needle valve seat, and the shutoff valve further includes a vertically-moveable member placed between the first motor and the first needle valve, and a vertically-moveable member placed between the second motor and the second needle valve, each of the vertically-movable members configured to be moved by driving of the corresponding first and second motors to relatively move the respective needle valve elements with respect to the needle valve seats.