Abstract: Provided is a magnetic marker which surely gives warning from a vibration receiving side, by surely generating vibration. A magnetic marker has a bent vibration plate and a flat vibration plate to be magnetostrictively vibrated in the main body of a case. On the main surface of an open section side of the case, a low coercive force magnet is arranged to be magnetized and demagnetized. The magnetic marker is attached to a commercial product and the like by peeling a peeling sheet of an adhesive tape. In the magnetic marker, as far as the low coercive force magnet is not demagnetized, two sheets of the vibrating plates magnetostrictively vibrate upon passing through a gate. Thus, the vibration receiving side is surely made to give warning.

Abstract: A magnetic sensor having a simple structure and high accuracy for detecting a linear or angular displacement thereof. A magnetic plate with tapered thickness is magnetized in a direction perpendicular to its surface. A magnetic sensor is arranged so that it can move in the direction of the taper of the plate thickness. A drive mechanism for this magnetic sensor is movable with an object to be detected, and the output of the magnetic sensor indicates the displacement.