Patent ID: 7148679
Filing Date: 2006-12-12
Classification: G01D,G01P

Abstract:
1. A transformer probe for sensing movement of a body of magnetic material comprising: a magnetically energisable pole piece; a sensing circuit comprising an electrical circuit having a first portion which is inductively coupled to the pole piece, the arrangement being such that movement of a body of magnetic material relative to the pole piece induces a current in the sensing circuit, and a second portion, remote from the pole piece, which forms a transformer primary coil; a transformer secondary coil, inductively coupled to the primary coil formed by the second portion of the sensing circuit, and terminated by a load resistance and means for measuring an output signal from the secondary coil, wherein the primary and secondary coils form a transformer such that a current in the sensing circuit induces a voltage across the secondary coil; and at least one shorting turn of a conductor is inductively coupled to the primary and secondary coils.