摘要 |
A feeder assembly for an alumina eletrolysis cell includes an alummina dose holder (5) defined between inner and outer walls (6, 7, 7') with an inlet port in the outer wall above an outlet port in the inner wall. The inlet and outlet ports (8, 11) are closable and openable by valve means formed by relative movement between the outer wall (7, 7') and a valve seat (10, 12) cooperating with a seating edge of the outer wall (7, 7'). The valve means is moved by drive means (13) including a pneumatically operated piston (14) movable within a cylinder (15) concentric with the shaft (2) of an electrolyte crust-breaking plunger (1). The plunger shaft (2) is axially slidable within an annular sleeve (18) of the piston (14) which is connected to at least one movable component of the valve means. |