Proportional solenoid-controlled fluid valve having compact pressure-balancing armature-poppet assembly

A solenoid-actuated valve assembly comprising:

• a solenoid coil having a longitudinal axis and a solenoid bore coaxial therewith, said solenoid coil producing a magnetic flux;
• a magnetic pole piece comprised of an axial portion, a lower distal end, and a sleeve piece portion, said magnetic pole piece supported within said solenoid bore and exclusive of the use of non-magnetic material, said sleeve piece portion further comprised of a relatively thin portion contiguous with said sleeve piece portion, said relatively thin portion rapidly saturating when said valve is subject to said magnetic flux;
• an axially translatable armature made of a magnetic material, said armature being supported substantially within an armature cavity for axial translation along said longitudinal axis, said armature forming an axial gap and a radial air gap with said magnetic pole piece, said armature magnetically coupled to said relatively thin portion of said magnetic pole piece, and said armature having an internal bore therethrough providing fluid communication with said solenoid bore;
• a valve unit, mechanically coupled to said armature, said valve unit having an interior valve poppet cavity in fluid communication with a fluid inlet port to which fluid is applied at a first fluid pressure and a fluid exit port from which said fluid is output at a second fluid pressure and containing a valve seat therebetween, said valve seat adapted to be closed by a valve closing assembly comprised of a valve poppet mechanically coupled to said armature, so as to regulate fluid flow between said fluid inlet port and said fluid exit port;
• an armature centering mechanism to prevent off-axis tilting of said armature;
• a fluid pressure balancing arrangement adapted to compensate for said first fluid pressure and said second fluid pressure being exerted against said valve poppet, said fluid pressure balancing arrangement comprising a diaphragm between said armature cavity and said interior valve poppet cavity and a fluid communication path through said valve closing assembly, said fluid communication path providing fluid communication between said fluid exit port and said armature cavity;
• and
• a spring disposed substantially within said solenoid bore of said solenoid coil and between said magnetic pole piece and said armature for biasing said armature away from said lower distal end of said magnetic pole piece.

A valve assembly comprising:

• a solenoid coil adapted to generate a magnetic flux, and having a longitudinal axis and a bore coaxial therewith;
• an axially translatable armature made of a magnetic material, said armature supported within an armature cavity for axial translation along said longitudinal axis;
• a magnetic pole piece disposed within said bore of said solenoid coil, said magnetic pole piece comprised of an axial portion, a lower distal end, and a sleeve piece portion, said magnetic pole piece being magnetically coupled to said armature and forming an axial air gap and a radial air gap between said armature and said lower distal end of said magnetic pole piece, and said sleeve piece portion further comprised of a relatively thin portion contiguous with said sleeve piece portion, said relatively thin portion rapidly saturating when said valve is subject to said magnetic flux;
• a valve unit, mechanically coupled to said armature, said valve unit having an interior valve poppet cavity in fluid communication with a fluid inlet port to which fluid is applied at a first fluid pressure and a fluid exit port from which said fluid is output at a second fluid pressure and containing a valve seat therebetween, said valve seat adapted to be closed by a valve closing assembly comprised of a valve poppet mechanically coupled to said armature, so as to regulate fluid flow between said fluid inlet port and said fluid exit port;
• an armature centering mechanism to prevent off-axis tilting of said armature;
• and
• a fluid pressure balancing arrangement adapted to compensate for said first fluid pressure and said second fluid pressure being exerted against said valve poppet, said fluid pressure balancing arrangement comprising a diaphragm between said armature cavity and said interior valve poppet cavity and a fluid communication path through said valve closing assembly, said fluid communication path providing fluid communication between said fluid exit port and said armature cavity.