1. Field of the Invention
The present invention relates to an alternator that is directly connected to an internal combustion engine, such as an alternator for use in a motorcycle.
2. Description of Related Art
Most of alternators for use in a four-wheel automobile are driven by an engine by a driving belt connecting an alternator pulley and a driving shaft of the engine, as exemplified in JP-A-2002-58193. In this case, air for cooling the alternator can be easily taken into the alternator and exhausted from the alternator without interfering with a bracket of the engine. Accordingly, the alternator is sufficiently cooled by the cooling air. In order to further improve cooling efficiency, it has been proposed to use conductor segments, as exemplified in JP-B2-3407643.
Some other alternators, such as alternators for use in a motorcycle, are directly connected to an engine and directly driven by the engine without using a pulley and a driving belt, as exemplified in JP-A-8-331786. In this case, a hot airflow exhausted from the alternator after cooling the alternator is hindered by an engine bracket that is closely located to the alternator. Accordingly, the hot air may be taken again into the alternator, and the alternator may not be sufficiently cooled.