Oscillator current supply for portable data appts. - delivers energy to primary coil with electromagnetically coupled detector coil for load change pick=up

摘要

The supply delivers energy from an oscillator circuit (10) to a primary coil for the energy transfer to a secondary coil (7), opposite to the primary coil (3) in a contactless manner by electromagnetic induction. To the primary coil is electromagnetically coupled a detector coil (12), picking up a load change, based on a distance variation between the primary and secondary coils. It transmits a signal obtained by a change of an induction voltage, due to the load change. In accordance to the induction voltage change, a control (4) energises an output of the oscillator circuit such that the energy received by the secondary coil remains constant. USE/ADVANTAGE - For portable electronic data appts., with stable supply current even with varying spacing or coils.