| 摘要 |
470,945. Inductances. KRAMOLIN, L. L. DE. Aug. 29,1936, Nos. 23733 and 23734. Convention dates, Aug. 29, 1935 and Nov. 8, 1935. [Class 38 (ii)] [Also in Groups XL and XXXVI] Constructions of polarizing magnets are described for the variable inductances used in the method of tuning a radio receiver described in Specifications 449,240 ; 451,097, [Group XXXVI], and 451,098, [Group XL]. In one embodiment, Fig. 3, the cores 15, 16 of two inductances are located between two pairs of polepieces of a common magnet, auxiliary windings 13a and/or 14a being provided to enable the inductances to be matched. The currents through the main and auxiliary windings may aid or oppose each other and the magnet may be permanently magnetized. Relatively pointed polepieces are used, the bearing surface being about the same width as the shanks of the core of the controlled inductance. Another form of polepiece is shown in Fig. 5. In another embodiment, Fig. 8, the inductance 15 is arranged in a cylindrical copper screen 29 between the internally projecting polepieces of a boxshaped core and surrounded by the magnetizing winding 14. |
