Device for supplying water for the further alluviation of fibres in strainers

Claim 1

AN IMPROVEMENT IN A PULP SCREEN INCLUDING AN ANNULAR SCREEN AND A ROTARY IMPELLER, A PULP STOCK INLET LOCATED AXIALLY WITH RESPECT TO SAID IMPELLER, A HOLLOW DRIVE SHAFT HAVING A SERIES OF AXIAL ROWS OF HOLES IN ITS SURFACE AREA AND MEANS TO SUPPLY DILUTION WATER TO SAID HOLLOW SHAFT, A SLEEVE HAVING TELESCOPED RELATIONSHIP WITH AND AXIALLY MOVABLE ALONG SAID SHAFT AND PROVIDED WITH AXIAL ROWS OF HOLES COINCIDING IN RADIAL AXIAL PLANES WITH ROWS OF HOLES IN SAID SHAFT, THERE BEING THE SAME NUMBER OF HOLES IN THE ROWS THEROF IN THE SLEEVE AND IN THE ROWS OF HOLES IN THE SHAFT, AND THE HOLES IN THE SLEEVE SAID SLEEVE AXIALLY ALONG SAID SHAFT, THE HOLES IN THE SLEEVE HAVING DIFFERENT DIMENSIONS IN THE DIRECTION AXIALLY OF THE SLEEVE AND SHAFT COMPARED TO THE HOLES IN THE SHAFT, WHILE THE CENTERS OF THE HOLES RECKONED FROM THE MIDDLE POINT OF THE ROWS TOWARDS BOTH ENDS ARE DISPLACED IN RELATION TO EACH OTHER IN SUCH A WAY, THAT WHEN THEY ARE IN A POSITION IN WHICH THE CENTERS OF THE HOLES IN THE AXIAL CENTER OF THE ROWS OF HOLES IN THE SHAFT AND SLEEVE COINCIDE, THE FLOW OF DILUTION WATER THROUGH EACH PAIR OF HOLES IS OF EQUAL MAGNITUDE, BUT WHEN THE SLEEVE IS DISPLACED IN EITHER DIRECTION WITH RESPECT TO THE SHAFT, SAID FLOW VARIES IN DIFFERENT DEGREES THROUGH THE COMMUNICATING PAIRS OF HOLES IN THE ROWS IN THE SHAFT AND SLEEVE.