Patent ID: 9659703
Date: 2017-05-23
CPC Classifications: H01F

Claim:
1. An ignition coil for an internal-combustion engine, comprising: an assembly of a primary coil wound around an outer circumference of a primary spool, a secondary coil wound around an outer circumference of a secondary spool and arranged concentrically on an outer circumference of the primary coil, and a central core disposed on an inner circumference of the primary coil; and a ring-shaped outer core surrounding the assembly of the primary coil, the secondary coil, and the central core, the outer core being in contact with a first axial end surface of the central core and forming a core gap between the outer core and a second axial end surface of the central core, the second axial end surface of the central core being opposite the first axial end surface of the central core, wherein the assembly comprises: at least one first protrusion protruding from a first end surface of the secondary spool on a first axial end side of the central core, the at least one first protrusion being in contact with an inside surface of the outer core and being offset from the central core toward a second opening of the outer core in a penetration direction of the outer core, the second opening of the outer core being opposite a first opening of the outer core from which the assembly of the primary coil, the secondary coil, and the central core are inserted into an inside of the outer core; and at least one second protrusion protruding from a second end surface of the primary spool opposite the first end surface of the secondary spool in the axial direction of the central core, the at least one second protrusion protruding beyond a second axial end surface of the central core opposite the first axial end surface of the central core in the axial direction of the central core so as to be in contact with the inside surface of the outer core and extending substantially the entire length of the outer core in the penetration direction.