Sedimentation tank having rotatable sediment conveying structure

Claim 1

IN A CONTINUOUSLY OPERATING SEDIMENTATION APPARATUS HAVING A SETTING TANK WITH OVERFLOW MEANS AT THE TOP AND SEDIMENT OUTLET MEANS AT THE BOTTOM, SEDIMENT CONVEYING APPARATUS WHICH COMPRISES (A) A VERTICAL CYLINDRICAL SHAFT CARRYING SEDIMENT RAKING MEANS AT ITS LOWER END PORTION, SAID SHAFT AND RAKING MEANS BEING ROTATABLE FOR MOVING SEDIMENT TO SAID OUTLET MEANS, SAID SHAFT BEING MOUNTED FOR SUBSTANTIAL VERTICAL SHIFTING MOVEMENT TO ADJUST THE RAKING MEANS TO VARYING WORKING CONDITIONS, SAID SHAFT HAVING A FIRST SET OF AT LEAST TWO VERTICAL GROOVES OF A LENGTH AT LEAST EQUAL TO THE DESIRED VERTICAL MOVEMENT OF THE RAKE MEANS, SAID GROOVES EACH BEING DISPOSED ENTIRELY WITHIN THE PERIPHERY OF SAID SHAFT AND BEING EQUALLY SPACED ABOUT THE SHAFT AXIS AND EACH HAVING SEMI-CIRCULAR CROSS-SECTIONAL PROFILE; (B) A DRIVE GEAR STRUCTURE CONCENTRICALLY ASSOCIATED WITH THE UPPER END PORTION OF SAID SHAFT, SAID DRIVE GEAR STRUCTURE HAVING A DOWNWARDLY DEPENDING TUBULAR GUIDE SURFACE SURROUNDING SAID SHAFT IN AXIALLY SLIDEABLE RELATIONSHIP WITH SAID SHAFT, SAID TUBULAR GUIDE SURFACE HAVING A SECOND SET OF VERTICAL GROOVES CONSIDERABLY SHORTER THAN SAID FIRST SET OF GROOVES, SAID SECOND SET OF GROOVES BEING ENDWISE CLOSED AND OF SEMI-CIRCULAR CROSS-SETIONAL PROFILE COMPLEMENTARY TO THE PROFILE OF SAID FIRST SET OF GROOVES, SAID SECOND SET OF GROOVES CONSTITUTING WITH SAID FIRST SET OF GROOVES RESPECTIVE COMPOSITE CYLINDRICAL SPACES, SAID SECOND SET OF GROOVES BEING DISPOSED ENTIRELY WITHIN THE INNER PERIPHERY OF SAID TUBULAR GUIDE SURFACE; (C) A TORQUE-TRANSMITTING MEMBER OF CIRCULAR CROSSSECTION LOCATED IN EACH SAID COMPOSITE CYLINDRICAL SPACE, EACH SAID TORQUE TRANSMITTING MEMBER HAVING A DIAMETER SLIGHTLY SMALLER THAN ITS RESPECTIVE COMPOSITE CYLINDRICAL SPACE, SAID TORQUE TRANSMITTING MEMBERS EACH BEING SUBSTANTIALLY CONFINED AGAINST LONGITUDINAL MOVEMENT IN SAID SECOND SET OF GROOVES, WHEREBY SAID FIRST SET OF GROOVES CONSTITUTE TRACKS FOR THE RESPECTIVE ASSOCIATED TORQUE TRANSMITTING MEMBERS WHEN SAID SHAFT IS AXIALLY SHIFTED RELATIVE TO SAID DRIVE GEAR STRUCTURE FOR RAISING AND LOWERING THE SEDIMENT CONVEYING RAKE MEANS IN THE TANK, WITH SAID TORQUE TRANSMITTING MEMBERS ADJUSTING THEMSELVES IN TANGENTIAL CONTACT WITH THEIR RESPECTIVE GROOVES TO EASTABISH BALANCED DRIVE TORQUE TRANSMISSION FROM THE GEAR STRUCTURE TO SAID SHAFT, WHEREBY RESISTANCE TO THE RAISING AND LOWERING MOVEMENT OF THE SHAFT UNDER TORQUE LOAD IS MINIMIZED; (D) A CASING STRUCTURE WHEREIN SAID DRIVE GEAR STRUCTURE IS MOUNTED FOR ROTATION; (E) HORIZONTAL SUPPORT STRUCTURE EXTENDING TRANSVERSELY OF THE TOP PORTION OF THE TANK FOR MOUNTING SAID CASING STRUCTURE AND SUPPORTING SAID SHAFT IN VERTICAL POSITION; (F) AND ACTUATING MEANS MOUNTED ATOP SAID DRIVE GEAR STRUCTURE AND CONNECTED TO THE UPPER END PORTION OF AND VERTICAL SHAFT FOR RAISING AND LOWERING SAID SHAFT AND SEDIMENT RAKING MEANS.