An electric magnet device comprising: a coil adapted to insert through at least one of an armature (71, 87, 92) and a yoke (50, 85, 91) so as to attract surfaces of the yoke (50, 85, 91) and the armature (71, 87, 92), which are opposed to each other, to receive a voltage, to excite for separating the surfaces of the yoke (50, 85, 91) and the armature (71, 87, 92); the armature (71, 87, 92) disposed on one end side of the coil and the yoke (50, 85, 91) disposed on the other end side of the coil, the armature (71, 87, 92) and the yoke (50, 85, 91) are configured to oscillate in directions relative to the coil, characterised in that the armature (71, 87, 92) and the yoke (50, 85, 91) oscillate between making and not making surface contact with each other and a portion of the armature (71, 87, 92) and/or the yoke (50, 85, 91) moves through the coil during oscillation, wherein the yoke (50, 85, 91) becomes inclined according to inclination of the armature (71, 87, 92) when the armature (71, 87, 92) is inclined and makes the surface contact with the yoke (50, 85, 91); and wherein an oscillation angle of the yoke (50, 85, 91) is greater than an oscillation angle of the armature (71, 87, 92), wherein when a ratio of the oscillation angle of the yoke (50, 85, 91) to the oscillation angle of the armature (71, 87, 92) is lesser than 1:1, the yoke (50, 85, 91) will not be able to contact the armature (71, 87, 92) during oscillation, and when a ratio of the oscillation angle of the yoke (50, 85, 91) to the oscillation angle of the armature (71, 87, 92) is greater than 3:1, the yoke (50, 85, 91) will be able to contact the armature (71, 87, 92) during oscillation with abrasion at surfaces of the yoke (50, 85, 91) and the armature (71, 87, 92) in contact. a coil adapted to insert through at least one of an armature (71, 87, 92) and a yoke (50, 85, 91) so as to attract surfaces of the yoke (50, 85, 91) and the armature (71, 87, 92), which are opposed to each other, to receive a voltage, to excite for separating the surfaces of the yoke (50, 85, 91) and the armature (71, 87, 92); the armature (71, 87, 92) disposed on one end side of the coil and the yoke (50, 85, 91) disposed on the other end side of the coil, the armature (71, 87, 92) and the yoke (50, 85, 91) are configured to oscillate in directions relative to the coil, characterised in that the armature (71, 87, 92) and the yoke (50, 85, 91) oscillate between making and not making surface contact with each other and a portion of the armature (71, 87, 92) and/or the yoke (50, 85, 91) moves through the coil during oscillation, wherein the yoke (50, 85, 91) becomes inclined according to inclination of the armature (71, 87, 92) when the armature (71, 87, 92) is inclined and makes the surface contact with the yoke (50, 85, 91); and wherein an oscillation angle of the yoke (50, 85, 91) is greater than an oscillation angle of the armature (71, 87, 92), wherein when a ratio of the oscillation angle of the yoke (50, 85, 91) to the oscillation angle of the armature (71, 87, 92) is lesser than 1:1, the yoke (50, 85, 91) will not be able to contact the armature (71, 87, 92) during oscillation, and when a ratio of the oscillation angle of the yoke (50, 85, 91) to the oscillation angle of the armature (71, 87, 92) is greater than 3:1, the yoke (50, 85, 91) will be able to contact the armature (71, 87, 92) during oscillation with abrasion at surfaces of the yoke (50, 85, 91) and the armature (71, 87, 92) in contact.