Hitachi, Ltd.

Hitachi Automotive Systems, Ltd.

Honda Motor Co., Ltd.

Makio Takahashi

Yoichi Anzo

Takanobu Kobayashi

Gakuji Moriya

Makoto Kurahashi

An object of the present invention is to provide an ignition coil for use in an internal combustion engine, offering improved water drainage performance, while achieving high waterproof performance with controlled entry of water in a plug hole. A high-voltage generating sectionthat generates a high voltage is housed inside a coil case. A plug hole sealcloses an opening in a plug holein which an ignition plugis mounted. The ignition coil further includes a space portionplaced on an outer side portion of the high-voltage generating sectionand an air pathfor venting air between the space portionand the plug hole. The space portionhas an open lower surface (an entirely open surface facilitates demolding).

Ignition coil for internal combustion engine

An auxiliary core portion and a main core portion, including a magnet if the magnet is attached, are covered by a resin film or an elastomer film and fixed as a single assembly. In this state, a coil is attached to the assembly and a side core portion is assembled to the assembly. The auxiliary core portion and the main core portion, including the magnet if it is attached, can be supplied, as the single assembly, to an automated assembly line for ignition coils. It is not necessary to position such components on the assembly line. Thus, the workability of the automated assembly can be enhanced.

An internal combustion engine ignition coil device has an annular seal rubber at its lower side coil. An annular projection is provided on a part of the seal rubber and is pressed against the inner diameter surface of a plug hole. An air path is formed in part of a coil case by mounting the seal rubber into a groove, enabling inside and outside portions of the plug hole to communicate. A gas-permeable thin film resin member is bonded to an inlet of the air path.

Growing community of inventors

Hitachinaka, Japan

Makio Takahashi