(under subclass 418) Apparatus in which the motor comprises a pair of working chambers for driving a single working member in opposite directions by the application of controlled pressure motive fluid to expand one chamber and to contract and expel exhaust motive fluid from the other chamber and in which the valve means controls a fluid line connecting the chambers to permit motive fluid to pass from one chamber to
the other, said valve means operating separately from the control of the pressure motive fluid.
(1) Note. The operation of the by-pass valve means, to be separate from the pressure motive fluid control, must operate in a manner inconsistent with the normal motor operation such that a double acting motor with a unitary spool valve having short lands which may interconnect opposed motor chambers at one valve position is excluded and will be found in subclass 464.
(2) Note. A double acting motor in which a valve controlled by-pass line is also constantly open to exhaust is considered to be a common exhaust and is excluded from this definition.
SEE OR SEARCH THIS CLASS, SUBCLASS:
16+, for expansible chamber motors with motive fluid supplied through diverse flow paths to a single expansible chamber in which the motor drifts or coasts on a lower motive fluid pressure.
