Solenoid operated fluid control valve

A solenoid assembly, comprising:

• coil means defining an internal bore bounded by a pair of axial ends,
• a frame member having a middle portion and first and second end flanges extending transversely from said middle portion, said end flanges defining respectively first and second apertures, said frame member disposed relative to said coil means such that said end flanges surround said axial ends of said internal bore,
• a pole piece disposed and fixed in said coil means bore and within said first aperture thereby defining a first clearance between said pole piece and said first end flange such that said pole piece and said frame member do not contact each other,
• an armature member disposed in said coil means bore and movable in said bore in response to energization of said coil means, said armature further disposed in said second aperture thereby defining a second radial clearance between said armature and second end flange, and
• first and second rings of polymeric resin material within said first and second radial clearances thereby preventing direct contact of said frame member with said pole piece and said armature.

A solenoid coil including a bobbin having an end flange and wherein said coil has start and finish end portions adjacent to said end flange, the improvement comprising:

• laterally spaced cavities in said end flange, and
• binding posts on said flange disposed intermediate and outboard of said cavities,
• said outboard binding posts being breakable from said flange,
• electrical terminal members having rearwardly extending, longitudinal mounting portions and wire clamping tabs disposing forwardly of said mounting portions, the mounting portions of said terminals adapted to be inserted into and to be retained by said cavities,
• the start and finish end portions of said coil wire adapted to be wrapped initially around and extended between said intermediate and outboard binding posts,
• said tabs being disposed to overlay the extended portions of said coil wire when the mounting portions of said terminals are pushed into said cavities and adapted further to be bent into clamping relationship with and welded to said extended wire portions and underlying portions of said terminal members, and
• said extended wire portions adapted to be snapped off at said tabs when said outboard binding posts are broken away from said flange.

A method of calibrating a solenoid operated valve of the type having a coil assembly defining an internal bore, a pole piece adapted to be inserted into said bore and in frictional engagement therewith, and an armature mounted for axial movement with said bore and relative to said pole piece coupled to a valve assembly having a valve element which controls fluid flow through a port, and spring means urging said armature away from said pole piece, comprising the steps of:

• providing a subassembly of said solenoid operated valve including said coil assembly, said armature and said valve assembly,
• supplying a fluid pressure signal to said port,
• applying a voltage signal to said coil assembly,
• loading said pole piece into said coil assembly bore,
• driving said pole piece into said bore,
• monitoring said fluid pressure signal, and
• stopping said driving when a change in state of said valve assembly occurs as determined by said fluid pressure signal, whereby the desired calibrated relationship betwen said pole piece and said armature is provided.