Nippondenso Co., Ltd.

Toshiyuki Yamaguchi

Akihiko Takenaka

Tiaki Mizuno

Miyao Arakawa

Masahiro Sato

Yoshiaki Nakano

Hiroyuki Nobechi

A rotation detecting apparatus includes a first electromagnetic pickup of the electromagnetic coil type positioned to face a single signal rotor in the diametrical direction thereof and generate a first rotation signal, a permanent magnet received in a recess formed in the principal plane surface of the signal rotor, and a second electromagnetic pickup including a magnetoresistance effect element positined separately above the upper surface of the permanent magnet and operatively associated with the magnet to generate a second rotation signal.

Electromagnetic rotation detecting apparatus

A contactless ignition system for an internal combustion engine comprises a signal generator generating an AC signal synchronously with the rotation of the engine, a resistor detecting primary current supplied to an ignition coil, a circuit detecting the rising time of the primary current until the primary current attains a predetermined level, and a circuit producing a signal proportional to the rotational speed of the engine. On the basis of the signal indicative of the rising time of the primary current supplied to the ignition coil and the signal proportional to the rotational speed of the engine, an off-time control signal for controlling the off-time of the ignition coil is generated in which the ratio between the duration of the primary current supplied to the ignition coil, being maintained at the predetermined level, and the ignition period is maintained constant. The off-time of the ignition coil is controlled only when the rotational period of the engine is shorter than a predetermined setting.

Contactless ignition system for internal combustion engine

Growing community of inventors

Okazaki, Japan

Toshiyuki Yamaguchi