| 摘要 |
PURPOSE:To always keep the optimum secondary air quantity by measuring the transport air quantity of a pneumatic unloader, the amount of transported granular powder and the transport air pressure and controlling the drive of a secondary air quantity adjust device of a suction nozzle according to the measured values. CONSTITUTION:The transport air quantity of a pneumatic unloader for unloading granular powder, the quantity of transported granular powder and blower suction pressure (transport air pressure) are measured by a differential pressure gauge 8, a pressure gauge 9 and a gravimeter 10. The measured values are input to a computer 20 to calculate the required secondary air quantity (drive signal). The calculated drive signal is sent to a secondary air quantity adjust devide 11, so that the adjust device 11 is automatically controlled in such a manner as to always obtain the best mixture ratio (weight of transported material/ quantity of air used for transport) during operation and the secondary air quantity of the pneumatic unloader is optimized to make best the efficiency of transposting granular powder. |
