| 摘要 |
PURPOSE:To increase the electrostatic capacity with no limitation given to the area of a mobile electrode by providing a pair of switch terminals to two fixed electrode respectively. CONSTITUTION:For this electrostatic capacity type keyboard, switch, the fixed electrostatic capacity is generated between fixed electrodes 7 and 8. At the same time, the variable electrostatic capacity is produced between fixed electrodes 8 and 9. This capacity is inceased as a mobile electrode 10 moves downward. In proportion to this increase of the capacity, the electrostatic capacity (equal to the capacity produced between electrodes 7 and 9) produced between switch terminal parts 7a and 9a approximates to the capacity produced between the electrode 7 and 8 and then finally becomes equal to said capacity. In addition, the electrodes 7 and 8 are arranged as shown in the figure to obtain the electrostatic capacity about several ten times as much as the conventional value owing to the areas of both electrodes as long as no limitation is given to the areas of electrodes 7 and 8. |
