Transformer for passing from electrically symmetrical systems to unsymmetrical systems and vice versa

摘要

600,627. Transformers. PATELHOLD PATENTVERWERTUNGS- & ELEKTROHOLDING AKT.-GES. April 5, 1945, No. 8455. Convention date, April 13, 1944. [Class 38 (ii)] In a transformer connecting symmetrical and unsymmetrical systems and having the centre of that winding which is connected to the symmetrical system and one end of the other winding at the same potential, the primary winding, which is in four series connected parts, comprises at least two cylindrical windings and the secondary at least one cylindrical winding, and one winding completely surrounds the other. In the construction shown in Fig. 2 the main parts f and g of the two windings are screened by the interposition of the central parts d 1 , d 2 of the centre tapped winding and the end part e of the other winding, these parts having a one to one transmission ratio. The voltage difference between the two screening winding parts is uniform along the turns, being the difference between - U to + U and o to 2u. In the limiting case as shown in Fig. 5 the winding s is not divided into a screening and another part, while the other winding p having four parts d 1 , d 2 , f 1 , f 2 is dimensioned for a transmission ratio of 1.7 : 1 suitable for the modulator stage in push-pull connection to high frequency stages, Fig. 1 (not shown). Fig. 8 shows the physical arrangement of such windings round a core shown by the dotted lines k 1 , k 2 . For a fine tuning of the oscillation circuits formed by winding sections d 1 , d 2 , f 1 , f 2 and their parallel capacitances, adjustable condensers can be located between the centre of this winding and the ends of the sections. Fig. 9 (not shown). For convenience of manufacture the four parts d 1 , d 2 , f 1 , f 2 may be made equal when the balance is not perfect.