(under subclass 521) Apparatus in which the means for controlling pump fluid flow into or out of two or more chambers comprises either (1) a single rigid unitarily movable valve member which moves from one position to another to alternately control the inlet to or discharge from said two or more chambers or (2) relatively movable inlet or discharge valve members which are mechanically interrelated in a manner such that movement of an inlet or discharge valve member for one pump chamber necessitates movement of an inlet or discharge valve member, respectively, for another pump chamber.
SEE OR SEARCH THIS CLASS, SUBCLASS:
491+, for plural pumping chambers having a common pumping member, said pumping member controlling the inlet or discharge port of two or more of said chambers.
512, for a single mechanically-actuated distributor element located within or carried by a pump piston which controls pump fluid inlet to or discharge from plural pump chambers.
516, for a single mechanically-actuated distributor element which controls pump fluid inlet to or discharge from plural pump chambers.
524, for plural pumping chambers including a valved piston and in which a common element forms an inlet or discharge valve for two or more chambers.
SEE OR SEARCH CLASS 91, Motors: Expansible Chamber Type,
178+, for an expansible chamber-type motor having a single valve unit controlling plural working chambers.
