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. 05, 1988
Filed:
Sep. 15, 1987
Itsuki Ban, Nerima-ku, Tokyo, JP;
Other;
Abstract
A single-semiconductor motor fan comprises a cylinder; a fixed armature with the central portion fitted over the lower end of the outer periphery of the cylinder and having a plurality of salient poles; a plurality of single-phase armature coils mounted on the armature; bearings fixed on the inner periphery of both ends of the cylinder; a rotary shaft rotatably supported by the bearings; a cup-shaped rotor fixed on the upper end of the rotary shaft; an annular magnet fixed on the inner surface of the rotor and magnetized into N and S poles having the same pitch as those of the salient poles, the N and S magnetic pole surfaces facing the salient pole surfaces with a space therebetween; a radial fan composed of a plastic cylinder fitted over a protruding portion of the rotor and a plurality of plastic plates extending radially outwardly of the cylinder, the height of the radial fan not exceeding the height of the protruding portion of the rotor; a position detecting element for detecting the position of the magnet of the rotor and producing a single-phase position detecting signal; an energization controlling circuit for energizing the armature coil and producing a unidirectional torque by the position detecting signal; and a self starting means for producing an output torque at a dead point by virtue of a cogging torque.