| 摘要 |
<p>An electronic liquid flow-measuring system comprising of a power source; a main electronic flow meter and a secondary liquid low flow electronic meter connected as a by-pass to said main meter; a microprocessor or for controlling flow measurements and the three position valve; a three position valve connected to both meters for closing said electronic main flowmeter at very low flows permitting only said secondary liquid flow meter to operate at low flows, such that at normal flows the valve is in its second position allowing the liquid to flow through both meters, and when the liquid flow is beyond a predetermined flow the valve is in its third position blocking all flow, and wherein said third position is achieved by means for opening a gate that permits the moving part of the valve to reach its third position and digital and analog processing means for producing readable numeric output values. <IMAGE></p> |
