摘要 |
<p>A machine unit (18-1) provided with an electrostatic retention means (2) is disposed at a desired position. The electrostatic retention means (2) includes a pair of electrodes (4, 6), an attraction member (8) associated with the pair of electrodes (4, 6) and in which static electricity is induced so as to generate an electrostatic attraction force which attracts and retains an object (12-1), and a power source circuit (10) for supplying positive and negative charges to the pair of electrodes (4, 6) while sequentially and alternately changing the polarity thereof.</p> |