Denso Corporation

Hidetoshi Nakashima

Kazutoyo Osuka

Kazuhide Kawai

Katsunori Akimoto

Jyunichi Wada

Yoshitaka Sato

Masahiko Aoyama

Masahiro Inagaki

Masafuyu Sano

Koji Tsunenaga

Hajime Kasai

Takashi Tauchi

Kaneo Buma

Shigeya Abe

In a stick coil, there is disclosed an ignition coil for an internal combustion engine which can prevent a crack (a collar leak) from being generated due to a thermal stress. In this ignition coil, the structure is made such that a size (L) of a portion which is in parallel to an axial direction of a primary spool ( ) in a projection portion ( ) is larger than a size (T) of a portion which is in parallel to an orthogonal direction to the axial direction of the primary spool ( ). Accordingly, a frontal projected area of the projection portion ( ) as seen from a flowing direction of a resin becomes small, a resin flow is hard to get out of order at a time when the resin flows through a portion corresponding to the projection portion ( ) at the forming time, and a convoluted void and a weld are hard to be generated. Accordingly, since it is possible to prevent a mechanical strength in a root portion of the projection portion ( ) from being reduced, it is possible to previously prevent a crack from being generated in the root portion of the projection portion (the collar portion) ( ) due to a thermal stress so as to reduce an insulating property.

Ingition coil for internal combustion engine

An ignition coil includes a center core, a primary coil a secondary coil, a coil housing, a tower housing disposed under the coil housing, and a high tension terminal disposed inside the tower housing. The high tension terminal has an upper flange disposed at a first circumferential gap opposite the inside surface of the tower housing and a middle barrel disposed at a second circumferential gap opposite the inside surface of the coil housing. The first circumferential gap is made smaller than the second circumferential gap. The tower housing or the upper flange has a void-purging passage for purging air from the insulation resinous members when filled in the coil housing.

Resin-insulated ignition coil

Growing community of inventors

Chiryu, Japan

Hidetoshi Nakashima