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Automatic swing device

  • US 6,908,398 B1
  • Filed: 02/23/2004
  • Issued: 06/21/2005
  • Est. Priority Date: 01/05/2004
  • Status: Expired due to Fees
First Claim
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1. A swing device comprising:

  • a supporter;

    a seat suspended on the supporter to swing in front and back directions;

    a permanent magnet installed in the seat; and

    an electromagnet installed to face the permanent magnet in a swing path to have the same polarity as that of the permanent magnet, wherein the electromagnet is selectively driven when the permanent magnet approaches, generating a repulsive force for the permanent magnet, and the electromagnet includes an iron core, a primary coil wound around the iron core, a power source for supplying electric current to the primary coil, and a switching unit disposed between the primary coil and the power source so as to selectively interrupt current supply from the power source to the primary coil.

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