摘要 |
The present invention relates to an apparatus having spaced permanent magnets (24, 54, 56) positioned so there is a magnetic interaction between them, and controlling the interaction by having a coil (26, 28, 30, 32, 34, 36, 38) in the space between the permanent magnets connected to a source of electric potential and a controllable switch in series such that closing the switch places voltage across the coil and predeterminately affects the magnetic interaction between spaced permanent magnets. The invention also teaches mounting one of the spaced permanent magnets on a rotatable structure so that the spaced permanent magnets can move relative to each other, the controllable switch operating to control the application of electric potential across the coil in such a manner as to produce relative rotational movement between the spaced permanent magnets. |