| 摘要 |
PURPOSE:To improve the reliability of an automatic meter inspecting device by constructing the device using a contactless sensor for automatic inspection of a water service meter. CONSTITUTION:The variation in the magnetic field due to the rotations of a permanent magnet 1 constituting a meter 1A is detected by a magnetic field sensor 2, which constitutes an oscillator 5 disposed in the vicinity of the meter 1A, so that positive and negative signals are generated from a drive circuit 3. The positive and negative half periods of the output signals are metered by a detecting circuit 7. From the positive and negtive half periods, the rotations of the permanent magnet are duduced by a judging circuit 8. The output of this circuit 8 is fed instantly to an inspecting center or stored in a memory, if necessary, so that the storage is fed to in response to the instruction from the inspecting center. By the use of such contactless senser, the reliability of the automatic meter inspecting device can be improved. |
