Machines of the liquid flow-type wherein the liquid within a fixed receptacle has a periodic surging action (i.e., a periodic to and fro motion) automatically controlled.
(1) Note. The pumping action may be caused by intermittently applied air or steam pressure.
(2) Note. See subclass 184 or other appropriate indented subclass where the mechanism periodically delivers the liquid in pulses primarily in the same direction, the mechanism not functioning to deliver a corresponding pulse in the opposite direction, and also for machines with nonautomatic (e.g., manual) means for causing reverse liquid pulses.
SEE OR SEARCH THIS CLASS, SUBCLASS:
51, for surgers combined with squeezers, and see the note to this subclass.
