| 摘要 |
In the starting position of the appts., the magnetic field-sensitive detector (10) is at a predetermined distance from the bottom (30) of the tank (3), and a stop (18) is located against a contact (19). Via a signal from an electronic unit (21), a drive motor (15) rotates rollers (14) in an anti-clockwise direction so that the vertically moving system (9) commences to move. At the same time, the stop moves downwards with the detector moving upwards. As soon as the stop moves away from the contact, a recording mechanism (20) receives a start signal, and commences recording the movement of a perforated tape (12) its monitor (24) probing the number of passing holes. Monitoring continues during the movement upwards of the magnetic field-sensitive detector, and when the latter passes a magnet (8) fitted in a float (7) it is activated to provide a stop signal to the recording mechanism via the electronic unit. |
