Honda Giken Kogyo Kabushiki Kaisha

Honda Motor Co., Ltd.

Denso Corporation

Hitachi Automotive Systems, Ltd.

Toyo Denso Co., Ltd.

Gakuji Moriya

Kenichi Ishida

Kazuyuki Kubo

Makoto Kurahashi

Toshihiro Ohkama

Kazuhide Kawai

Katsunori Akimoto

Yoichi Anzo

Shoji Kishi

Makio Takahashi

Takanobu Kobayashi

Takahiro Kajihara

Toshihiro Okama

Tomoyuki Kimura

Yoshihito Ozawa

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

In an ignition coil for an internal combustion engine, a column section and a notched section are provided in a side wall section of a case section of the ignition coil. A ventilation opening is formed in an up/down direction in the column section. The ventilation opening communicates with a ventilation passage formed between a sealing rubber and the case section and is open in an upper end section. A cover surrounding the column section and covering the upper end section is provided in the side wall section. A sealing section sealing the notched section is provided in the cover. The ignition coil has a filler resin that fills a space within the case section being in continuous contact with the sealing section and the side wall section and fixing the cover to the side wall section.

Ignition coil for internal combustion engines

In a plughole waterproofing device for an engine, a coil case is fitted onto the ignition coil that is accommodated in a plughole of an engine, and an upper portion of the case protruding above the engine is provided with a longitudinal air path extending upward from a lower end thereof communicating with the plughole and a vent hole communicating with an upper end portion of the air path and opened to ambient air. A cover wall hanging while surrounding the vent hole is continuously provided on the case upper portion, and an air chamber is formed inside the cover wall, the vent hole being opened in an upper portion of the air chamber, and an opening face being formed at an entire bottom of the air chamber opening toward the engine.

Plughole waterproofing device for engine

A spark plug for internal combustion engine, which produces a spark discharge that ignites air-fuel mixture in the combustion chamber and causes combustion such that an ionic current flow during combustion can be utilized for detecting misfire of the engine. The spark plug the core connected to an ignition coil, a center electrode made of at least one of iridium and an iridium alloy and connected to the core through a seat, and a ground electrode separated from the center electrode with a gap. A sum of surface areas of the seat and the center electrode is not less than a prescribed value, specifically, is not less than 11.0 mm, and more specifically, is not less than 11.47 mm. Even when the diameter of the center electrode is reduced in the interest of improving ignition performance, improved ignition performance and improved ionic current detection accuracy can be achieved simultaneously.

Spark plug for internal combustion engine

In a system for detecting misfire for an internal combustion engine wherein ionization current that flows following the discharge current is detected and integrated during a period (gate) and occurrence of misfire of the engine is detected based on the integrated value, a processing delay circuit is provided which inputs at least one of the discharge current or the ionization current and based on the inputted current, delays starting of the period by a time point which is not earlier than termination of the discharge current. With this, the system is unaffected by fluctuation in ignition coil discharge period, various kinds of noise and the like, and can therefore ensure accurate misfire detection by preventing erroneous detection owing to such causes.

Misfire detection system for internal combustion engines

A firing or ignition state discrimination system for an internal combustion engines having a spark plug which produces spark discharge when supplied with discharge current from an ignition coil to ignite air-fuel mixture in the combustion chamber. In the system, ionic-current that flows during combustion of the air-fuel mixture is detected at a predetermined first timing and leakage current that flows across electrodes of the spark plug is detected at a predetermined second timing which is later than the predetermined first timing. The firing or ignition state of the engine is discriminated to one from among normal, misfiring, spark plug fouling, and failure in ignition system or in fuel supply system based on the detected ionic-current and leakage current and presence or absence of fuel cutoff to the engine. With this, it becomes possible to accurately discriminates the firing or ignition state of the spark plug and to inform the fact to the vehicle operator if desired.

Firing state discrimination system for internal combustion engines

An ignition coil unit to be installed in a hole opened through a cylinder head of an engine having a case, an ignition coil installed in the case and comprising a primary coil connected to a power source and a secondary coil connected to a spark plug which is installed in a combustion chamber of a cylinder of the engine for producing spark discharge to ignite air-fuel mixture to generate combustion thereof in the combustion chamber, and a circuit board on which an ionic-current detection circuit, connected to the secondary coil, which detects ionic-current that flows during the combustion of the air-fuel mixture; and a processing circuit, connected to the ionic-current detection circuit, which generates an output indicative of the detected ionic-current, are formed; In the unit, an igniter is also installed in the case, thereby improving detection accuracy of ionic-current and misfiring.

Growing community of inventors

Wako, Japan

Gakuji Moriya