Patent ID: 6840258
Filing Date: 2005-01-11
Classification: F15B,F16P,Y10T

Abstract:
1. A method of resetting a double valve comprising the steps of: connecting a source of pressurized fluid to a reset port; actuating first and second reset pistons in response to said pressurized fluid to reset first and second movable valve units of said double valve, respectively; venting first and second pilot chambers when said first and second reset pistons are actuated, said first and second pilot chambers corresponding to first and second pilot valves for actuating said first and second movable valve units, respectively, wherein said venting prevents said first and second movable valve units from moving out of a deactuated position, respectively; removing said source of pressurized fluid from said reset port; retracting said first reset piston so that said second pilot chamber receives pressurized fluid while said first pilot chamber continues to be vented; retracting said second reset piston after a predetermined delay time following retraction of said first reset piston, said predetermined delay time being sufficient to allow said second pilot chamber to become substantially pressurized; and if said second pilot valve is actuated when said second reset piston is retracted, then said pressurized fluid in said second pilot chamber driving said second movable valve unit out of a deactuated position during a time that pressurized fluid in said first pilot chamber is insufficient to drive said first movable valve unit out of a deactuated position.