Electric tachometer sender

Claim 1

A TRANSFORMER COMPRISING A UNITARY SHELL STRUCTURE OF HIGH DIELECTRIC MATERIAL INCLUDING A THIN MEMBRANE AND HOLLOW PORTIONS CLOSED BY THE MEMBRANE AND EXTENDING THEREFROM IN OPPOSITE DIRECTIONS, A FIRST CORE RECEIVED IN ONE OF THE HOLLOW PORTIONS AND ENGAGING ONE SIDE OF THE MEMBRANE, A SUBSTANTIALLY IDENTICAL SECOND CORE RECEIVED IN THE OTHER HOLLOW PORTION AND ENGAGING THE OTHER SIDE OF THE MEMBRANE, AN ANNULAR RECESS IN EACH CORE FACING THE MEMBRANE, FIRST AND SECOND COILS RECEIVED IN THE RECESSES OF THE FIRST AND SECOND CORES, AND A HIGH DIELECTRIC SEALING COMPOUND FILLING THE SPACE IN THE SHELL STRUCTURE NOT OCCUPIED BY THE CORES AND COILS, THE MEMBRANE AND ADJACENT CORES FORMING A LOW RELUCTANCE MAGNETIC PATH FOR FLUX PRODUCED BY CURRENT IN ONE OF THE COILS, THE MEMBRANE, THE HOLLOW PORTIONS AND THE SEALING COMPOUND FORMING A HIGH RESISTANCE LEAKEAGE PATH WITHSTANDING HIGH POTENTIAL DIFFERENCES EXISTING BETWEEN THE COILS.