The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 07, 1989
Filed:
Mar. 26, 1987
John P Karidis, Ossining, NY (US);
Joseph P Pawletko, Endwell, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Alternately stacked radial-pole stator and spacer laminations provide a simple linear actuator, in which alternating layers form magnetic teeth in the axial direction. The spacer laminations are non-ferromagnetic or dimensionally spaced from the flux path. The stator laminations have radially extending pairs of poles, forming a central hole which may be filled and ground smooth along with the spacers, forming smooth pole faces upon which the armature may slide. Flux paths are coplanar with stator laminations, thus making each lamination completely independent. Electromagnetic force increases linearly as stator laminations are added. The stacked stator laminations have pole faces each having a finite pole face flux capacity; related armature rings can be mounted on a nonmagnetic support tube and made as light as possible so long as each ring is of sufficient cross-sectional area to carry half the pole face flux capacity. Tubular armatures provide maximum rigidity as a function of mass and permit the use of a stationary rod armature support for the tube armature. The support rod may be ferromagnetic to carry some of the flux, thereby further reducing the cross-section and the mass required for each ring.