(under subclass 437) Apparatus in which the control means comprises a distributor, and in which the extent or movement of said distributor toward open or closed position or the relation of the movement of the valve with respect to the pumping member may be varied by means which may be selectively moved and held in different positions.
SEE OR SEARCH THIS CLASS, SUBCLASS:
297+, for condition responsive means to vary the operation of a distributor for an expansible chamber pump.
427, for a plurality of pumps including means to adjust the distributor movement of one or more of the pumps.
524+, for separate means to bias a pressure responsive distributor to open position.
