Patent ID: 7049918
Filing Date: 2006-05-23
Classification: G01D,G01P,H01F

Abstract:
1. A magnetizing method for tone wheel, comprising the steps of: preparing a ring reinforcement made of magnetic material and attached to an annular body to be magnetized, said ring reinforcement comprising a tubular part and an other part integrally formed with said tubular part; holding said tubular part of said ring reinforcement with a fixing means comprising a jaw type chuck means made of non-magnetic material; and applying an alternate magnetic flux to said annular body while axially rotating said fixing means, keeping one end of a magnetizing yoke approximate to the surface of said annular body, said alternate magnetic flux forming a circular closed loop which passes said one end of said magnetizing yoke and the other end of said magnetizing yoke, via said annular body and said ring reinforcement midway, whereby said annular body is magnetized in a manner that S poles and N poles are alternately formed along its periphery.