| 摘要 |
PURPOSE:To detect rotational speed securely, by a method wherein a filter circuit is used without adding an external mechanism such as a rotary encoder. CONSTITUTION:A magnet 2 is attached to the inner wall of a cabinet 1, and arranged to surround an armature (rotor) 3. A rotary shaft 4 to penetrate the center portion of the armature 3 is held by bearings 5, 6 on both sides. An armature winding is connected to a commutator 8 mounted on the rotary shaft 4, and connected through a brush 9 to DC power source 10 which is connected to terminals A, B. A terminal C drawn from the cabinet 1 is connected to a filter circuit 12, and an output of the filter circuit 12 becomes rotation information output (rotation detection signal). In this constitution, the rotation information signal taken from the germinal C is entered into the filter circuit 12, and beard-like noise is removed. As a result, the output taken from the filter circuit 12 becomes noiseless pulse and the rotational speed can be securely counted. |
