Apparatus for determining the grain size of soils

摘要

The invention is an apparatus making it possible automatically to pipette from aqueous suspensions of soil in order to determine the silt and clay contents, and to wash this suspension in order to obtain the sand content. It consists of a tank 1 with an inclined bottom on which a motorised 4 bridge 3 moves, which carries the sampling syringes. The filling of the test vessels is under gravity from a constant-level tank 7 via solenoid valves 8. The siphoning is carried out by this same circuit using solenoid valves 8'. The agitation of the suspensions is effected with compressed air via the solenoid valve 22. The whole of this system is driven by a programmable automation system and is intended in particular for agricultural analysis laboratories in which it is desired to automate the granulometry. <IMAGE>