| 摘要 |
<p>PURPOSE: To enable an accurate one hand operation by integrating motion encoding and a generation means of selection signals not to have to operate the push buttons or other selection devices which are separated. CONSTITUTION: On a selection device B, a track ball is mounted on rolls 12 and 14 in a free rotatory state. The rolls 12 and 14 are connected to rotation encoders 16 and 18 respectively which generate pulse trains. Up/down counters 20 and 22 change the pulse into a linear motion instruction that goes along a bi-axis. A converter 50 outputs electric signals regarded as selection signals when the track ball is affected by downward non-rotation pressure. The converter 50 is the one whose strain gauge or output amount changes itself according to the strength of force. A comparison device 54 instructs whether to generate a selection signal by comparing the output of the converter 50 with a selectable threshold. A converter in another execution example has a binarization state, e.g. it changes states when it exceeds the prescribed minimum value by responding to affecting force to the track ball, 10 by means of a mechanical switch.</p> |
