Purification device for alkali metal cells

Claim 1

IN A FUSED SALT ELECTROLYSIS CELL, HAVING A RISER PIPE EXTENDING ABOVE THE CELL FOR CONCURRENTLY DISCHARGING SODIUM METAL, FOR COOLING AND PRECIPITATING THE CALCIUM IMPURITY AND RETURNING SAME TO THE CELL, AND HAVING IN COMBINATION WITH SAID RISER PIPE AN AUTOMATIC TICKLER ASSEMBLY WHICH INCLUDES A CLEANER DEVICE EXTENDING INTO THE VERTICAL RISER PIPE, AND MOTOR MEANS OPERATIVELY CONNECTED THEREWITH FOR IMPARTING VERTICAL RECIPROCATION AND ROTATIONAL MOTION OF THE CLEANER DEVICE WITHIN SAID RISER PIPE, THE IMPROVED CLEANER HAVING AN ELONGATED MEMBER OF LENGTH APPROXIMATELY EQUAL THAT OF THE RISER PIPE, A PLURALITY OF ARMS MOUNTED ON SAID MEMBER AND PROJECTING AT SUBSTANTIALLY RIGHT ANGLES THEREFROM AND SPACED ALONG SAID MEMBER, AND ARCUATE CLEANER BLADES HAVING EDGES BEVELED IN THE DIRECTION OF ROTATIONAL MOTION AND THE EDGES INCLINED TOWARD THE RISER PIPE WALL, AFFIXED TO THE EXTREMITIES OF SAID ARMS, SAID BLADES BEING ADJACENT TO AND ARCED TO CORRESPOND GENERALLY T O THE CURVATURE OF THE INNER SURFACE OF THE RISER PIPE, THE SUMMATION OF THE VERTICAL DIMENSIONS OF SAID BLADES BEING SUBSTANTIALLY EQUAL TO THE VERTICAL DIMENSION OF THE RISER PIPE WHEREBY ROTATION OF THE CLEANER CLEANS SUBSTANTIALLY THE ENTIRE INTERNAL AREA OF THE RISER PIPE.