| 摘要 |
PURPOSE:To provide a simple demagnetizing system being automatic, eliminating the need for a particular control system, reducing the number of components, and for having less trouble, operated by a d.c. power source being used for electromagnetic chucks of machine tools. CONSTITUTION:An electromagnetic chuck 1 being indicated as a series circuit comprising a resistance R and an inductance L is connected via a switch 2 to a d.c. power source on the voltage E. A switch 4 having a reverse polarity to said switch 2 against said power source 3 and being connected to the electromagnetic chuck 1 is placed. A condenser 5 having a capacitance C satisfying the inequality of R<2>/ 4L<2 1/LC is situated between said switch 4 and the electromagnetic chuck 1, whereby a RLC series circuit is formed on the side of the switch 4. A resistance 7 having a low resistance value R0 and used for discharge is connected in parallel to said condenser 5 via a switch 6. |
