Patent ID: 7392799

Claim:
An ignition coil comprising: a primary coil that includes a primary spool, which is made of a resin to have an annular cross section, and which has a first spool end portion and a second spool end portion, the primary coil including a primary winding, which is wound on an outer periphery of the primary spool, wherein the primary winding has a first winding layer that is wound around the primary spool from the first spool end portion toward the second spool end portion of the primary spool, wherein the primary winding has a second winding layer, which is continued from the first winding layer, and which is wound around the first winding layer from the second spool end portion toward the first spool end portion of the primary spool, wherein the primary spool has first and second overhangs, which protrude radially outwardly from an outer periphery of the first spool end portion of the primary spool, the first overhang being positioned away from the second overhang toward the second spool end portion, wherein the first overhang is one of a plurality of first overhangs that are circumferentially arranged at the outer periphery of the first spool end portion of the primary spool, wherein the first winding layer has a first winding end portion for a start of winding, which extends from the first winding layer through a space between the first overhangs, and which is wound on the outer periphery of the first spool end portion between the first overhang and the second overhang, and wherein the second winding layer has a second winding end portion for an end of winding, which extends from the second winding layer between the first overhangs, and which is wound on the outer periphery of the first spool end portion between the first overhang and the second overhang; and a secondary coil that generates high voltage when the primary coil is energized.