Patent ID: 8360097
Filing Date: 2013-01-29
Classification: F16K,Y10T

Abstract:
1. A valve actuator for adjusting the position of a main valve element in relation to the pressure of a fluid supplied by a supply duct, the valve actuator comprising: a housing, comprising: a control pressure valve disposed in the inner structure of the housing and configured to substantially impede fluid flow into control pressure chamber until the pressure of the fluid within the supply duct surpasses a minimum actuation pressure; a piston slidably disposed in the housing and configured to be mechanically coupled to the main valve element, the piston normally residing in a first position and configured to move toward a second position as the pressure within the control pressure chamber increases, the piston having a cavity in which the inner structure and control pressure valve are received when the piston is in the first position; and a piston spring disposed in the housing and biasing the piston toward the first Position, the pressurized fluid directed into the control pressure chamber through the control pressure valve exerting a cumulative force on the piston urging the piston toward the second position in opposition to the piston spring.