| 摘要 |
<p>PURPOSE:To directly generate thrust power in coils so as to drive a stage with high accuracy by arranging plural permanent magnets on a yoke in parallel to each other, and arranging plural coils on the stage to supply the coils with electric current. CONSTITUTION:A stage 3 slides on the guide face 2 of a base 1 under the guidance of air pads 4a, 4b, 4c by interaction between permanent magnets and coils. Permanent magnets 8a - 8d are arranged parallel to X-axis and in Y-direction at a fixed pitch of Po, and the coils 11 for X are arranged parallel to X-axis at a pitch of Po/2. The coils for Y are arranged similarly at a pitch of Po/2 to reverse the polarity of each of plural adjacent permanent magnets arranged in stripe manner. Electric current is selectively supplied to the coils arranged on the permanent magnets so as to constantly excite the coils arranged at the places of high magnetic flux density for the coils to efficiently generate force. The stage can be driven at high accuracy by allowing the coils fixed to the stage to directly generate thrust.</p> |
