| 摘要 |
1,256,438. Zone-melting. SIEMENS A.G. 18 March, 1970 [19 March, 1969], No. 12943/ 70. Heading B1S. In an apparatus for zone melting by means of induction heating the centre tap of the induction coil (one turn or a solenoid) is maintained at the same potential as the crystal rod (of, e.g. silicon or germanium) being treated so as to reduce the possibility of flashover. In the embodiment shown the centre tap 113 of the coil 107 is connected to the wall of the metal melting chamber, both this and the crystal support being earthed, the induction coil being powered by high-frequency generator 110 via capacitors 115. Other embodiments described have either an inductive or a capacitative symmetrising circuit with an earthed centre tap, (Figs. 2a, 2b, 2c and 3) or a centre tap of the coil coupling the heating circuit to the generator earthed (Fig. 2d), the crystal rod in each case being earthed. As an alternative to earthing in all cases the centre taps may be connected by a contact tongue to the crystal rod supports (Fig. 3). |
