| 摘要 |
Apparatus has a receiving chamber subjected to low pressure to receive solid/liquid mixture through inlet valve thereof. The chamber also has outlet valve to discharge the mixture, an admitting valve to raise pressure in the chamber, and quantity sensing structure responsive to predetermined quantity of mixture within the chamber. The inlet valve is positioned above a predetermined upper level of mixture within the chamber, and a riser constrains the mixture to move initially upwardly and then, optionally, downwardly prior to discharging through the inlet valve. The riser is shaped to cause solids that might otherwise tend to rest initially adjacent the inlet valve, when the mixture flow therethrough ceases, to fall under gravity either forwardly through the inlet valve, or backwardly towards mixture within the delivery duct. Time delay structure delays the opening of the admitting valve to raise pressure in the chamber sometime after attaining the predetermined quantity of the mixture, which also delays closing the inlet valve which provides time for solids to clear the inlet valve before closure thereof. The time delay structure uses either a reservoir for a single chamber embodiment, or for a twin chamber embodiment, the remaining chamber serves also as a reservoir. Use of a reservoir or chamber increases the time required for sufficient low pressure to be attained to actuate the admitting valve. Use of twin chambers provides means to receive mixture essentially continuously. |
