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:
Dec. 07, 2004
Filed:
Sep. 26, 2002
David B. Cope, Medfield, MA (US);
Andrew M. Wright, Somerville, MA (US);
Engineering Matters, Inc., Newton, MA (US);
Abstract
A miniature actuator, e.g., for use in a Micro Air Vehicle, comprises at least one nested array of magnets, with an outer annular magnet with a magnetization pointing in an axial direction, a middle annular magnet with a radial magnetization, and an inner cylindrical magnet with a magnetization directed anti-parallel to the magnetization of the outer annular magnet. In one embodiment, a permanent magnet actuator comprises such an array, and a conductive coil having a current distributed over the volume of the conductive coil, wherein the magnetic field of the array is perpendicular to the current located in the coil. The coil may be located above or below the first magnetic array. In another embodiment, a conductive coil is disposed between two magnetic arrays. The coil may have a winding that is pancake-shaped, solenoidal, or toroidal and may comprise more than one winding. The magnetic arrays may be canted to permit the toroidal winding to expand, affording control over the spread of the magnetic field in the gap.