A patent for a water pump assembly that can be connected to an underground water pump, which can make the pump rod extending into the well reciprocate.
the last sentence: it contains an elongated beam, which means that this pump assembly is composed of an elongated straight beam. Beam means beam, and I guess the function of this long beam is to connect an assembly above and below the well.
I am not engaged in machinery. The above suggestions are for reference only.