Abstract: The flow restrictor is a unitary one-piece element that can be fabricated from either metal or plastic by casting or molding. In use, it is press fitted into a bore in a solenoid valve body to provide a certain restrictive effect. It has a circular cylindrical central core that has a series of flanges that are axially spaced by gaps. Each flange has a circular outer edge that is interrupted by at least one axially extending through-notch. These notches are arranged to provide a tortuous path for the fluid flow, and sized to create a desired restriction. The restrictor provides two parallel flow paths, one, the tortuous path just described, and two, a through-hole through the core of the restrictor.

Abstract: The armature has a circular cylindrical main body that is surrounded at one axial end by a circular flange. The flange can conduct what would otherwise be stray magnetic flux and because the flange is on a substantial radius, it can provide a significant area for the magnetic flux even though the flange's radial dimension is small. A number of channels are formed in the armature to provide for passage of fluid past the armature.

Abstract: A solenoid coil is fabricated by precisioin winding a length of bondable magnet wire on a mandrel, heating and axially compressing the precision-wound convolutions to cause the bondable insulation to deform into a unitary, void-free mass, but without deforming the pre-existing circular cross section of the conductive metal core of the wire, and allowing the wire to cool such that the mass immovably captures the convolutions of the conductive core to thereby form a free-standing coil. The coil is then disposed in a mold cavity where the entirety of the coil is encapsulated. This produces a solenoid coil that is well-suited for use in high-pressure "wet" environments because the encapsulated assembly is strong and leak-proof. The encapsulant may be molded in such a manner as to have no seams extending from its surface to the winding.