(under the class definition) Apparatus in which the device is provided with a mass of material rotatable with the working member and positioned so that it at least partially opposes unbalanced forces of either (1) the rotating working member or (2) a movable part thereon moving incident to the expansion and contraction of the working chamber.
SEE OR SEARCH THIS CLASS, SUBCLASS:
210, for devices in which axially spaced rotating working members counterbalance each other.
