Liquid cleaning system including back-flushing filter and centrifugal cleaner therefor

A liquid cleaning system comprising pump means operable to cause liquid to flow through the system, a barrier filter having a back-flush arrangement whereby a proportion of the liquid after passage through the barrier filter is passed in a reverse direction through a region of said barrier filter to create a back-flushed liquid;

• a fluid-powered centrifugal cleaner including a rotor having a contaminant chamber through which the back-flushed liquid is passed;
• and rotor drive means responsive to a supplied fluid, separate from the back-flushed liquid for effecting rotation of the rotor about a substantially vertical axis at at least a minimum speed required to effect centrifugal separation of solid contaminants from the back-flushed liquid passing through the contaminant chamber;
• and wherein the fluid-powered centrifugal cleaner comprises a housing having
• a base, defining a discharge region at ambient pressure, and
• spindle means, comprising
• a static spindle extending along an operably vertical axis through the housing,
• a bearing tube, carrying the rotor affixed thereto, journalled to the spindle and defining between axially spaced journals an annular tube space apertured to communicate with the contaminant chamber, and an axially extending main inlet passage formed in the spindle communicating with the annular tube space by way of main radial aperture means and arranged to receive said back-flushed liquid, and further wherein
• said fluid powered rotor drive means comprises
• a first part comprising an auxiliary inlet passage, extending along the spindle to receive therein said drive fluid separate from the back-flushed liquid, and auxiliary radial aperture means, spaced axially from the main radial aperture means, communicating with said bearing tube space, and
• a second part comprising rotor seal means, extending between the bearing tube and spindle at an axial position between the main and auxiliary radial aperture means to separate the tube space into discrete main and auxiliary regions, and a plurality of tangentially directed fluid reaction nozzles,
• and a plurality of drive conduits individually connecting said drive nozzles to the auxiliary region of the tube space to direct said drive fluid from the auxiliary inlet passage to the reaction nozzles.