Circuit for the production of an open alternating magnetic field
AssigneeSachs-Systemtechnik GmbH
InventorsHans-Peter Doetsch, Klaus Thiele
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Abstract
In an induction energy transfer device comprising a static power conversion circuit for producing an alternating magnetic field of ultrasonic frequency of the type wherein the static power conversion circuit includes a parallel resonant circuit which comprises a coil which also couples power across an air gap, an improvement in efficiency and power transfer is obtained by including at least two such parallel resonant circuits in the power conversion circuit, one of which resonant circuits is tuned to the third harmonic of said fundamental frequency.
Claims10
In a circuit for the production of an open magnetic field of the type comprising a generator with at least two transistors connected in push-pull, each transistor having base, emitter and collector terminals, the output of said generator being connected to resonant circuits having coils which simultaneously act as the induction coil of the open magnetic field, the improvement comprising a first resonant circuit having a coil tuned to a fundamental frequency by means of a parallel capacitance and a second resonant circuit connected in series with the first resonant circuit and having a coil which is tuned to the third harmonic of the fundamental frequency by means of a second parallel capacitance, whereby the two coils are constructed and arranged in such a manner that the fundamental frequency tuned resonant circuit and the third harmonic wave tuned resonant circuit are not mutually attenuating and additional means for supplying a suitably square voltage wave obtained through addition of the two resonance voltages produced, in suitable time relation to the collector current terminals of said generator.
Dependencies are inferred from the claim text.