Backwash system for diluting apparatus

摘要: Improvements in a backwash system for diluting apparatus wherein rinse solution is directed to the fluid transfer valve thereof and thence back through sample pick-up probe receptacle then waste depositary. The mounted on carrier, turn movement track from recessed condition, along path first outward upward engage delivery end of tight sealed coupling. A plunger an air cylinder effects track. vacuum operated switch employed assure that will not be dispensed as unless coupling made. Alternatively, microswitch can substituted presented carrier actuated when has moved sufficiently establish between probe. In either instance, scanned ascertain its state actuated, prevented.