Ignition coil unit with ignition voltage detective capacitor for

Abstract

An ignition coil unit for an internal combustion engine for containing an ignition voltage detective capacitor for misfire discrimination, including a core, a primary and a secondary coil wound around the core, and a case housing the core and the primary and secondary coils which is filled with an insulative material. In this unit, a first conductive electrode plate is placed in the case and electrically connected with the output of the secondary coil, and a second conductive electrode plate is also placed in the case in parallel with the first conductive electrode plate while maintaining a predetermined distance therefrom. An insulator is interposed between the first and second conductive electrode plates forming a capacitor that uses the insulator as the dielectric. When the first plate is fixed to the coil's bobbin at a position close to the secondary coil's higher voltage end such that it cantilevers therefrom, a partition or the like is interposed between the plates so as to prevent the first plate from interfering with the second plate.