| 摘要 |
<p>A crank angle sensor comprises a magnetic recording medium (30) rotating synchronously with a crank shaft on which magnetic signal are recorded and a magnetic sensor (4) provided opposite to the magnetic medium (30) and detecting the magnetic signals to produce a rotational angle information. The magnetic recording medium (30) is divided into plural tracks ( 31, 32); an angle track (31) and a cylinder track (32), for example. On the angle track (31), unit magnetic poles serving as the magnetic signals are provided in a pitch P corresponding to an angle to be detected. For each magnetic signal on the cylinder track (32) there is consecutively provided some of the same unit magnetic poles as those in the angle track (31) in the pitch P at locations which are determined by the number of cylinders of the engine. The polarities of the unit magnetic poles on the cylinder track (32) are in the same arangement as those of the unit magnetic poles of the angle track (31).</p><p>According to the invention, since no magnetic interference occurs between the unit magnetic poles of the angle track (31) and the cylinder track (32), angle signals and cylinder signals can be obtained with high accuracy.</p> |
