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:
Jul. 25, 1978
Filed:
Oct. 17, 1977
Abstract
A miniature coreless motor in which the coil of the rotor is wound in hollow cylindrical shape rotatable within an air gap between a cylindrical permanent magnet and a cup-shaped yoke, the yoke having pole-pitch zones of alternate polarity. The winding is wound progressively so as to be turned back alternately at the respective end edges to form axially re-entrant bends with the convolutions of the winding forming an inner layer of wire and an outer layer of wire, each convolution being made up of elements which are angularly related so that each convolution passes through pole-pitch zones of different polarity. The elements forming the inner and outer layers of wire cross one another at an angle to form a thin cylindrical two-ply construction in which the end edges are rigid and occupy parallel planes. One of the end edges has the axially-facing insulation superficially removed to expose a conductive surface at the outer periphery of each re-entrant bend. A pair of brushes of resilient spring metal provide localized axial contact with the exposed conductive surfaces of the winding at peripherally spaced points.