| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a keyboard apparatus in which even when a key laterally shifts on a keyboard structured to detect a key moving by using a magnetic sensor, influence of the lateral shift never appears in the position detection signal of the magnetic sensor. <P>SOLUTION: The keyboard apparatus comprises: the key which is supported to freely swing; a sensor arm which is supported below the key turnably along the same plane of turn as the plane of turn of the key and has its free end in contact with the lower part of the key to turn by a turning quantity corresponding to the depression quantity of the key; an energizing means which is extended between the sensor arm and key and applies an elastic displacing force to the sensor arm and key to maintain turning free ends of both key and sensor arm at higher positions; the magnetic sensor which is arranged at a fixed part facing the turning free end of the sensor arm at the turning position of the sensor arm corresponding to the maximum depression position of the key; and a magnet which is mounted on a magnet mount part provided at the turning free end of the sensor arm and applies a magnetic field gradually varying in accordance with the depression quantity of the key to the magnetic sensor as the key is depressed. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
