| 摘要 |
<p>An apparatus and method for producing cyclic motion of a recording element, such as a hammer (30), by energization of an electromagnet (36) or by a permanent magnet to a saturation point of the element material to cause the recording element to move towards the magnet. The magnetic field (40) is then reversed and the polarity in the element initially opposes the magnetic field to enable a controlled repulsion force and causes the recording element to move in an opposite direction. The magnitude of the reversing field then causes the element to change its polarity and to be realigned with the magnetic field causing the element to be moved towards the magnet. Magnetic hysteresis is thus utilized in the repulsion and attraction of such an element in both directions of movement. </p> |
