Abstract: A linear actuator for pumping comprising a stator having an inner opening, a shaft having a plurality of permanent magnets spaced linearly in the axial direction, the shaft disposed in the stator opening and configured to reciprocate linearly in the axial direction relative to the stator, the stator comprising a first stator assembly having a plurality of pole sections spaced linearly in the axial direction and a plurality of coils disposed therebetween, a second stator assembly having a plurality of pole sections spaced linearly in the axial direction and a plurality of coils disposed therebetween, a bearing assembly positioned axially between the first stator assembly and the second stator assembly, and the bearing assembly having a width that is a function of the spacing of the plurality of pole sections of the first stator assembly and the second assembly and the spacing of the plurality of permanent magnets of the shaft.

Abstract: A method of assembling a shaft of a magnetic motor comprising the steps of providing a plurality of magnets (210), providing a plurality of pole pieces (212), stacking (S11) said magnets and pole pieces to form a subassembly (202) having an outer surface of a first diameter, providing a precipitation hardenable stainless steel sheet material, forming said stainless steel sheet material into a tube (S20), drawing said tube to form a precision tube having an inner surface of a second diameter (S21), said second diameter being greater than or equal to said first diameter, heat treating said precision tube to form a tubular sleeve of a Rockwell C hardness of at least about 40 and a magnetic permeability of at least about 100 (S22), and inserting said subassembly axially into said sleeve (S30), thereby forming a shaft for a magnetic motor.

Abstract: A linear actuator for pumping comprising a stator having an inner opening, a shaft having a plurality of permanent magnets spaced linearly in the axial direction, the shaft disposed in the stator opening and configured to reciprocate linearly in the axial direction relative to the stator, the stator comprising a first stator assembly having a plurality of pole sections spaced linearly in the axial direction and a plurality of coils disposed therebetween, a second stator assembly having a plurality of pole sections spaced linearly in the axial direction and a plurality of coils disposed therebetween, a bearing assembly positioned axially between the first stator assembly and the second stator assembly, and the bearing assembly having a width that is a function of the spacing of the plurality of pole sections of the first stator assembly and the second assembly and the spacing of the plurality of permanent magnets of the shaft.

Abstract: A method of assembling a shaft of a magnetic motor comprising the steps of providing a plurality of magnets (210), providing a plurality of pole pieces (212), stacking (S11) said magnets and pole pieces to form a subassembly (202) having an outer surface of a first diameter, providing a precipitation hardenable stainless steel sheet material, forming said stainless steel sheet material into a tube (S20), drawing said tube to form a precision tube having an inner surface of a second diameter (S21), said second diameter being greater than or equal to said first diameter, heat treating said precision tube to form a tubular sleeve of a Rockwell C hardness of at least about 40 and a magnetic permeability of at least about 100 (S22), and inserting said subassembly axially into said sleeve (S30), thereby forming a shaft for a magnetic motor.