| 摘要 |
<p>An hydraulic actuator of a constant pressure fluidic supply system is disclosed in which a movable shuttle disposed within a generally cylindrical housing forms therewith a plurality of piston and cylinder assemblies. Displacement of the shuttle within the housing is governed substantially by opposing hydrodynamic and hydrostatic forces balanced so as to selectively isolate a pump control pressure switch from system pressure during periods of moderate to high consumption demand and provide communication therewith during periods of low to zero consumption demand. An hydropneumatic tank or a conventional diaphragm tank may be used in combination with the actuator to provide fluidic capacitance to the system. Additional system valving and pressure regulation may be incorporated as desired. In alternative embodiments, pump stop time-delay mechanisms and pressure tanks may be employed. Electrical switches may be used in place of pressure switches. <IMAGE></p> |
