Method for forming multi-laminate core assembly

Claim 1

A method of forming a laminate core comprising a multiplicity of magnetic plates arrayed in face-to-face relation in a stack having opposite end surfaces, a generally circumferential outer side surface, and an axial bore sized and adapted for receiving a rotor, at least one of said outer side and bore defining surfaces also defining a multiplicity of notches sized and configured for receiving windings, said method comprising: assembling said plates in said stacked relationship; applying at least one strip of adhesive material generally axially along the outer surface of the assembled stack in an area not defining a said notch; allowing said adhesive to dry in a manner to hold said plates assembled during handling at least during application of bonding material prior to a curing step; thereafter applying, in powdered form, a bonding material in the form of a layer of dry particles of a thermoset synthetic resin to the surfaces of the assembly of plates defining said notches, said particles forming a layer covering the side surfaces of the discrete plates, and extending across spaces between adjacent plates in said stack, particles of said resin entering the spaces between said plates; and heating said stack to a temperature at least sufficient to cure said synthetic resin to form an integral bonding layer upon the surfaces of the stack defining said notches, and extending into the gaps between the plates of said stack; the cured thermoset resin forming said plates into a substantially rigid unit not subject to movement between layers during handling or at elevated temperatures of use; and, after said resin is cured sufficiently to hold said plates assembled, removing at least a portion of said adhesive.

Claim 2

A method of forming a laminate core comprising a multiplicity of magnetic plates arrayed in face-to-face relation in a stack having opposite end surfaces, a generally circumferential outer side surface, and an axial bore sized and adapted for receiving a rotor, at least one of said outer side and bore defining surfaces also defining a multiplicity of notches sized and configured for receiving windings, said method comprising: assembling said plates in said stacked relationship; applying at least one strip of adhesive material generally axially along the outer surface of the assembled stack in an area not defining a said notch; allowing said adhesive to dry in a manner to hold said plates assembled during handling at least during application of bonding material prior to a curing step; thereafter applying, in powdered form, a bonding material in the form of a layer of dry particles of a thermoset synthetic resin to the surfaces of the assembly of plates defining said notches, said particles forming a layer covering the side surfaces of the discrete plates, and extending across spaces between adjacent plates in said stack, particles of said resin entering the spaces between said plates; and heating said stack to a temperature at least sufficient to cure said synthetic resin to form an integral bonding layer upon the surfaces of the stack defining said notches, and extending into the gaps between the plates of said stack; the cured thermoset resin forming said plates into a substantially rigid unit not subject to movement between layers during handling or at elevated temperatures of use; and, after said resin is cured sufficiently to hold said plates assembled, removing at least a portion of said adhesive.