Ignition coil for internal-combustion engine
AssigneeHitachi, Ltd.
InventorsTakanori Sato, Ryozo Takeuchi
Life of this patent
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Abstract
An ignition coil for an internal-combustion engine has satisfactory electrical insulation capacity and is excellent in reliability and durability. The ignition coil for an internal-combustion engine comprises a primary bobbin on which a primary coil is wound, a secondary bobbin on which a secondary coil is wound, and a center core. The area of a cross section of the center core perpendicular to an axis of the coils at a position on the inner side of the opposite ends of the center core is a maximum.
Claims14
An ignition coil for an internal-combustion engine, comprising:
- a primary bobbin on which a primary coil is wound;
- a secondary bobbin on which a secondary coil is wound;
- and
- a center core;
- wherein an area of a cross section of the center core perpendicular to an axis of the coils at a position on the inner side of opposite ends of the center core is a maximum.
An ignition coil for an internal-combustion engine, comprising:
- a primary bobbin on which a primary coil is wound;
- a secondary bobbin on which a secondary coil is wound;
- and
- a center core;
- wherein a cross section of the center core at the middle of the center core has a maximum sectional area, and the sectional area of at least one of the opposite ends of the center core is smaller than that of a cross section at the middle of the center core perpendicular to an axis of the coils.
An ignition coil for an internal-combustion engine, comprising:
- a primary bobbin on which a primary coil is wound;
- a secondary bobbin on which a secondary coil is wound;
- and
- a center core;
- wherein the sectional area of at least one of the opposite ends of the center core is smaller than that of a cross section at the middle of the center core perpendicular to an axis of the coils, and the sectional area of the other end of the center core is equal to that of the cross section at the middle of the center core.
An ignition coil for an internal-combustion engine, comprising a center core having one end of a small area and the other end of a large area:
- wherein a permanent magnet of a large sectional area is disposed on the end having the large area of the center core, a permanent magnet of a small sectional area is disposed on the end of the small area of the center core, and the permanent magnets create magnetic fields of a polarity reverse to that created by a primary coil.
An ignition coil for an internal-combustion engine, comprising:
- a center core;
- a secondary bobbin surrounding the center core;
- and
- a primary bobbin surrounding the center core;
- wherein the secondary bobbin or the primary bobbin has wall thickness increasing from a middle portion toward an end on the side of a high-potential end.
An ignition coil for an internal-combustion engine, comprising:
- a center core;
- a secondary bobbin surrounding the center core;
- and
- a primary bobbin surrounding the center core;
- wherein the inside diameter of the secondary bobbin or the primary bobbin decreases from a middle portion toward an end on the side of a high-potential end.
An ignition coil for an internal-combustion engine, comprising:
- a center core;
- and
- permanent magnets disposed on the opposite ends of the center core, respectively;
- wherein the sectional areas of the permanent magnets are greater than the area of a smaller one of the opposite ends of the center core, and smaller than the maximum sectional area of the center core.
An ignition coil for an internal-combustion engine, comprising:
- a primary bobbin on which a primary coil is wound;
- a secondary bobbin on which a secondary coil is wound;
- and
- a center core;
- wherein the diameter of the center core is decreased stepwise from a middle portion toward one end of the center core.
An ignition coil for an internal-combustion engine, comprising:
- a primary bobbin on which a primary coil is wound;
- a secondary bobbin on which a secondary coil is wound;
- and
- a center core;
- wherein a thickness of a portion of at least one of insulating members on a high-tension side is greater than that of a portion of the insulating member on a low-tension side.
An ignition coil for an internal-combustion engine, comprising:
- a primary bobbin on which a primary coil is wound;
- a secondary bobbin on which a secondary coil is wound;
- and
- a center core;
- wherein a magnetic flux density in at least one of opposite ends of the center core is approximately equal to that in a middle portion of the center core.
Dependencies are inferred from the claim text.