Patent ID: 8011639
Filing Date: 2011-09-06
Classification: F16K,Y10T

Abstract:
1. A valve comprising: a valve body having an inlet, an outlet, and a flow passage in direct connection with said inlet and said outlet, said inlet, said outlet and said flow passage generally extending axially through said valve body, wherein said inlet defines an opening of said flow passage and said outlet defines an opening of said flow passage; a valve seat surrounding the flow passage; a poppet-type valve closure member axially mounted to a stem, said poppet type valve closure member movable towards the valve seat to close the valve, said poppet type valve closure member movable away from the valve seat to open the valve and said stem having a plurality of pistons spaced apart along the length thereof; a plurality of cylinders fixed relative to said valve body, each of said pistons being slidable in a respective cylinder, said valve closure member being movable by varying the pressure in said cylinders, each of said cylinders is supplied with high pressure operating fluid by a pilot valve controlled source of high pressure fluid, said pilot valve supplies high pressured operating fluid to each of said cylinders, and during said pilot valve off cycle time, said high pressure operating fluid is not supplied to each of said cylinders; an outlet port disposed from each of said cylinders through said respective cylinder wall and into said flow passage, each of said outlet ports being exposed when said closure member has moved towards or into a fully open position, each of said outlet ports being configured to dissipate said high pressure operating fluid from said cylinder into said flow passage when said outlet port is exposed during the off cycle time of said pilot valve; and an end cap disposed at an end of said valve opposite said valve closure member, said end cap forming an end wall of one of said cylinders, a bleed passage disposed in the end cap, said bleed passage for bleeding high pressure fluid from said one of said cylinders to said flow passage.