Patent ID: 7242118
Filing Date: 2007-07-10
Classification: H02K

Abstract:
1. A toroidal-coil linear reciprocating motor comprising: an armature having a toroidal coil and a pair of armature yokes made from magnetic material to hold said toroidal coil; a cylindrical element having a magnetic structure facing said armature through an air gap in a radial direction, said cylindrical element enabling linear relative movement with respect to said armature in an axial direction; an axis for supporting one of said armature and said cylindrical element; and a housing for supporting said axis, the other of said armature and said cylindrical element being coaxially fixed to said housing, wherein each of said pair of armature yokes has a single toroidal magnetic tooth that is formed as a projection on the surface facing said cylindrical element, and said magnetic structure of said cylindrical element has two pairs of permanent magnets of S pole and N pole that are fitted on a cylinder portion of said cylindrical element made from magnetic material, one pair of said permanent magnets can face said toroidal magnetic tooth of one of said armature yokes and the other pair of said permanent magnets can face said toroidal magnetic tooth of the other of said armature yokes, and wherein said two pairs of permanent magnets are arranged so that one toroidal magnetic tooth faces N pole of one pair of permanent magnets when the other toroidal magnetic tooth faces S pole of the other pair of permanent magnets, and wherein magnetic force acted between said armature and said magnetic structure of said cylindrical element generated by the energized toroidal coil relatively reciprocates one of said armature and said cylindrical element along said axis with respect to said housing, or relatively reciprocates one of said armature and said cylindrical element together with said axis with respect to said housing.