Denso Corporation

Other

Yoshihiro Shimoide

Kazuhide Kawai

Kazutoyo Oosuka

Kazutoyo Osuka

Norihiro Adachi

Yoshihiko Shiraishi

Masami Kojima

Katsunori Akimoto

Yoshitaka Sato

Jyunichi Wada

Tohru Nomura

Toshiyuki Shinozawa

Masafuyu Sano

Koji Tsunenaga

Atsuyuki Konishi

Osamu Sugie

Yoshitaka Satou

Rikiya Kamimura

Kaneo Buma

Hiroshi Kasugai

Shigemi Itou

Masaharu Shimohata

Shuichi Matsubayashi

A thick film circuit board that can be produced at a low cost, a method of producing the same, and an integrated circuit device. A first thick film circuit board has conducting layers of a copper-containing conductor fired at not higher than 750&#xb0; C., and includes conducting portions formed by using a silver-containing conductor. A second thick film circuit board has conductors that are formed in the through holes so as to close the openings of at least the one side thereof. The thick film circuit board is produced at a low cost and suppresses a drop in electric conductivity when it is in use.

Thick film circuit board, method of producing the same and integrated circuit device

An interesting coil supporting unit for an engine includes an elongated casing and a plurality of coil units. Each coil unit has a coil support portion and an ignition coil. The coil support portions are disposed inside the casing at predetermined intervals. The casing and the respective coil support portions are fastened to a cylinder block by means of a plurality of bolts. In this state, each coil unit is supported by the corresponding bolt so as to be slidable in its radial direction. Therefore, the coil units can be positionally slid in the casing and thereby installed easily on the engine.

Integrated coil supporting unit slidably holding ignition coil units

In an ignition coil assembly, a plurality of ignition coils is arranged to be electrically connected to spark plugs received in plug holes of an engine. A base cover includes a plurality of receiving through holes, which are arranged at corresponding positions that correspond to positions of the plug holes, respectively. A top cover covers a top surface of the base cover and secures each ignition coil through engagement with the head of each ignition coil. Fastening bolts temporarily fasten the top cover and the base cover in a manner that allows sliding adjustment of a securing position of each ignition coil, which is loosely received in a corresponding one of the base cover through holes, in an imaginary plane that is perpendicular to an axis of each ignition coil.

Ignition coil assembly for engine

An ignition coil includes a housing which contains a central core portion, an inner spool having a first winding, and an outer spool having a second winding. The inner spool extends outward of the central core portion. The outer spool extends outward of the inner spool. A locating member includes a locating rib adjacent to an upper portion of the central core portion. The locating rib is in a gap between the inner spool and the central core portion, and locates the inner spool and the central core portion relative to each other. Insulating resin injected into the housing provides insulation among parts in the housing. At least one of the inner spool and the locating member has a void-escape passage which connects the gap and an outside of the inner spool with each other, and which allows a void to escape from the injected insulating resin in the gap.

Ignition coil

In order to prevent a crack of plastic parts caused by a shrinkage force of a resin filler filled in an ignition coil casing, a cylindrical coil casing houses a primary coil and a secondary coil concentrically, and the resin filler such as epoxy resin is filled in the coil casing to insulate between the parts in the coil casing and to fix the parts. A ring-shaped partition member is provided at the upper portion in the coil casing to separate the resin filler locating above the primary coil and the secondary coil inside and outside. The partition member is made of a resin whose adhesive strength against the resin filler is weak, such as polypropylene (PP). The partition member reduces the shrinkage force between the outside resin filler and the inside resin filler, and prevents a crack of plastic parts, such as the secondary spool.

A stick-type ignition coil device has a central core, and primary and secondary windings wound concentrically around the central core in a coil casing. A positioning part is provided in the casing to define the position of the central core. An insulating resin such as epoxy resin is filled in the coil casing for electrical insulation and fixing of components in the coil casing. A thermal stress releasing member, which is less adhesive to and easily peelable from the insulating resin, is provided on the upper surface of the positioning part. The thermal stress releasing member is separated from the insulating resin and allows the positioning member to move with the central core, thereby minimizing cracks which will occur in the insulating resin formed between the central core and the positioning part.

Stick-type ignition coil device having thermal stress releasing member

An ignition coil that can be easily assembled, that assures co-axial alignment of a primary coil, a secondary coil and a center core part, and that generates desired high voltage. A core body is formed to have an outer diameter larger than that of a permanent magnet so that the permanent magnet will not protrude out of the outer peripheral face of the core body. Accordingly, when the center core part is inserted into a secondary spool, the center core part is not caught by the secondary spool and may be readily inserted and assembled therewith. Also, because no bulge is created at the center core part, it is possible to prevent the center core part from tilting within the secondary spool and to readily assure the co-axial alignment of the primary spool, the secondary spool and the center core part. Thus, voltage generated by the secondary coil is prevented from dropping, and high voltage may be applied to the ignition plug.

Ignition coil for internal combustion engine

An ignition coil has a coil case made of an insulating resin, including a head portion, a cylinder portion accommodating a primary coil, and a secondary coil and a high-voltage tower portion for fitting with a spark plug. At least one of those three portions is separately molded and then the portions are assembled to form the coil case. The longitudinal length of each of the three portions is less than a forming flow length of the insulating resin, thereby preventing inferior molding. Further, the structure of each molding die is simpler than that of the coil case for an integral molding. Therefore, the coil case of the ignition coil can be molded readily without molding defects, even when the coil case is elongated, formed thinner, and/or formed with an undercut portion.

Ignition coil having coil case

An ignition coil for an internal combustion engine, having a seal between the ignition coil and a plug hole of the engine. An air passage is provided only on a head portion and a pipe portion of the ignition coil to permit air to pass. Pressure change in the plug hole can be equalized with the atmosphere through the air passage. Therefore, it becomes easy to make the seal and to attach the seal to the ignition coil because the seal does not have any air passage.

Growing community of inventors

Chita-gun, Japan

Yoshihiro Shimoide