Active magnetic seal

A process for providing dynamically controlled magnetic gaps between stator and rotor faces to control leakage along a rotating shaft, said process comprising:

• fixing a radially extending rotor ring with opposing side surfaces to said shaft, said side surfaces being connected by an axial extending surface;
• providing stator ring elements with radially extending surfaces spaced from and facing said side surfaces of the rotor ring, said stator elements including axially extending circumferential grooves in said radially extending surfaces;
• providing electromagnet windings in said grooves and extending axially form said grooves such that a gap is formed between each winding and said rotor side surfaces;
• sensing the linear gap displacements at each said rotor side surface, and in response to said sensing;
• supplying electrical power to said windings of an appropriate magnitude and polarity as to magnetically correct axial displacements between said stator elements and said rotor ring so as to control said gaps to have substantially equal displacements, said displacements being sufficiently small as to effectively control leakage along said shaft.

A rotating shaft sealing apparatus comprising:

• rotor ring means carried on said shaft for providing radially extending sealing surfaces connected by an axially extending surface;
• stator ring means for providing radially extending surfaces located adjacent to said rotor means radial surfaces, said stator ring surfaces including circumferential grooves;
• ring-shaped electrical winding means extending from said grooves toward said rotor ring radial surfaces for forming dynamically controllable magnetic boundary sealing gaps;
• electrical control means for detecting the relative differences in the axial gap dimensions and for applying power to said windings to exert a corrective action whereby said axial gap dimensions are maintained substantially equal.