| 摘要 |
PURPOSE:To make it possible to follow up the rapid variation of liquid level, by providing a spring pulley combined with a winding pulley in one body and a constant output pulley wound round by the spring pulley. CONSTITUTION:When liquid level is rising slowly, a motor 10 is driven in winding direction by a displacement signal from a detecting element 7, a ratchet wheel 22 being engaged with a ratchet turns a winding pulley 20, and the winding pulley 20 keeps winding a tape 13 until a required tension is obtained. When the liquid level is descending, the winding pulley 20 is turned to drawing out direction. When the liquid level ascend abruptly the winding pulley 20 is turned in the tape coiling direction by spring force of a constant spring 25. When the liquid level has gone down, the winding pulley 20 is turned in the tape drawing out direction. |
