Ignition coil

An ignition coil comprising:

• a coil main body portion that generates a high voltage;
• a conductive member that electrically connects the coil main body portion and a terminal metal fitting of a spark plug;
• and
• a protective portion that has an electrically insulating property, the conductive member being arranged inside of the protective portion, wherein
• the conductive member includes an elastic portion that elastically deforms in a longitudinal direction of the conductive member, and a conductive terminal that is arranged on a distal end side of the elastic portion,
• the conductive terminal has a distal end surface that includes a convex surface that abuts on the terminal metal fitting of the spark plug, the convex surface being formed to protrude toward a distal end side toward an inner circumference side, a contact portion between the convex surface and the terminal metal fitting of the spark plug having an annular shape.

An ignition coil comprising:

• a coil main body portion that generates a high voltage;
• a conductive member that electrically connects the coil main body portion and a terminal metal fitting of a spark plug;
• and
• a protective portion that has an electrically insulating property, the conductive member being arranged inside of the protective portion, wherein:
• the conductive member includes an elastic portion that elastically deforms in a longitudinal direction of the conductive member, and a conductive terminal that is arranged on a distal end side of the elastic portion;
• the conductive terminal has a distal end surface that includes a concave surface or a convex surface that abuts on the terminal metal fitting of the spark plug, the concave surface being formed to be recessed toward a proximal end side toward an inner circumference side, the convex surface being formed to protrude toward a distal end side toward the inner circumference side, a contact portion between the concave surface or the convex surface and the terminal metal fitting of the spark plug having an annular shape;
• the elastic portion is configured by a coil spring that stretches and contracts in a longitudinal direction of the conductive member;
• the conductive terminal includes a small diameter portion of which an external form when viewed in the longitudinal direction is smaller than that of a portion adjacent to the small diameter portion on a proximal end side;
• and
• a distal end portion of the coil spring is wound around the small diameter portion by a single turn or more.