| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a desirable liquid pump system eliminating unexpected liquid drop by devising a structure preventing liquid drop by suck back action of a pump. <P>SOLUTION: The liquid pump system includes a pump P for liquid, a delivery valve 28, and a suction valve 27, and can change over a drive state to a suction drive state in which the delivery valve 28 is closed, the suction valve 27 is opened and the pump P is operated for suction, and a delivery drive state in which the delivery valve 28 is opened, the suction valve 27 is closed and the pump P is operated for delivery, and a delivery. In change over from the delivery drive state to the suction drive state, the delivery valve 28 is opened with accompanying completion of the delivery drive state, and the drive state is changed over to the suction drive state via a reverse drive state in which the pump P is operated for suction with closing the suction valve 27. In change over from the delivery drive state to the reverse drive state, the pump P is immediately changed over from delivery operation to suction operation with maintaining the open state of the delivery valve 28 and the close state of the suction valve 27. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
