| 摘要 |
In drum pumps, the intake is formed by the cross-sectional area of a narrowed end of an external pipe, in which a non-return valve is provided. The pump's capacity is reduced by the valve. In the new pump, the reduction in pressure and output caused by the reduced cross-section of the intake is intended to be compensated for, at least approximately. In order to increase the pumping output and compensate for pressure losses, a supplementary intake is provided, which is open when vessels are being pumped out. While the vessel is being pumped out, the liquid is sucked in through the intake and through the supplementary intake, as well. Once the liquid level in the vessel has sunk to the level of the supplementary intake, it is closed, so that no air is taken in through the supplementary intake. The liquid is then sucked in through the intake. The pump ensures a high output, although the intake that can be closed with the non-return valve has only a small cross-section.
|
