Patent ID: 7159843

Claim:
In a solenoid-controlled valve having a seat around a valved opening, a seal arranged to engage the seat to close the valved opening, an armature holding the seal for movement out of and into engagement with the seat, a spring supporting the armature for movement and biasing the armature toward a closed valve position, and a solenoid arranged to move the armature against the spring bias to open the valve, the improvement comprising: the spring being flat and generally washer-shaped with a generally circular outer and inner perimeters that are each larger than the seat and concentric with the seat; the outer perimeter being secured to a body of the valve; the inner perimeter supporting the armature for axial movement during which the armature has no sliding engagement with any valve surface; the solenoid being arranged to apply a magnetic force to an armature perimeter that is larger than the seat and concentric with the seat; the inner perimeter being secured within a groove in the armature; the outer perimeter being trapped in a groove in the valve body allowing the outer perimeter to move slightly as the inner perimeter moves axially; and the spring being formed of a non-stretchable material that allows only axial translational movement of the armature between open and closed positions.