| 摘要 |
A method of, and apparatus for, energizing electromagnetic vibrators. An electromagnetic vibrator, driven by an electromagnet, is energized directly from an electric mains supply line carrying alternating current at a particular frequency. The electromagnet is operated at a fraction greater than one-quarter, and preferably equal to two-thirds or two-fifths, of the supply frequency such that the current drawn from the mains supply is substantially alternating current. |
