Patent ID: 6725877
Filing Date: 2004-04-27
Classification: F16K,F23N,Y10T

Abstract:
A solenoid valve for delivering a fluid at a variable flow-rate, comprising:a duct having and inlet opening and an outlet opening through which the fluid can pass substantially without changing direction, a valve seat within the duct, between the inlet opening and the outlet opening, a closure member movable between a closure position and a fully-open position, electromagnetic means for acting on the closure member in order to move it to any position between the closure position and the open position, in dependence on an electrical control quantity, the electromagnetic means comprising a core of ferromagnetic material, fixed firmly to the closure member and movable substantially along the same axis as the fluid, and a solenoid for generating a force on the ferromagnetic core along the same axis, and a further valve seat, a further core of ferromagnetic material, a further closure member fixed firmly to the further core, and further resilient means having dimensions such that, when the solenoid is not energized, the further closure member is urged against the further valve seat in order to block the passageway for the fluid and, when the solenoid is energized, the further closure member is removed from the valve seat to allow the fluid to pass through.