发明名称 EDDY CURRENT PREVENTER FOR PUMP
摘要 PURPOSE:To prevent a pump from eddy current to run the pump under the optimum conditions and improve reliability of the pump by detecting the occurrence of the eddy current in a suction water tank to control the running of the pump according to this detecting signal. CONSTITUTION:When depth Ha to which a pump 3 is immersed is reduced gradually, eddy current 8a occurs on water surface 2 and the pump 3 produces abnormal phenomena such as pressure variation, vibration and noise. These phenomena are detected by eddy current detectors 9a, 9b the detecting signals 10a, 10b of which are amplified by a amplifier 11 and then sent to the input of a computing circuit 12. Signals from the computing circuit 12 is sent to the input of a decision circuit 13 in which, when the occurrence of eddy current is recognized, a control 14 is operated by the signal of the decision circuit 13 to control a flow regulating valve 6 and reduce discharge amount of the pump 3. Thus, inflow speed of water sucked from a pump suction port 3a is also reduced so that the eddy current 8a is eliminated and the pump can be run under the optimum conditions.
申请公布号 JPS5888481(A) 申请公布日期 1983.05.26
申请号 JP19810185348 申请日期 1981.11.20
申请人 HITACHI SEISAKUSHO KK;HITACHI SANKI ENGINEERING KK 发明人 OOMAE ATSUSHI;MARU SABUROU;HARADA ICHIROU;SUDOU SUMIO
分类号 F04D29/66;F04B49/10 主分类号 F04D29/66
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