| 摘要 |
Self-cleaning sealing device for a piston 2 arranged in a cylindrical material container, generally horizontal, said piston being intended for displacing material in a material compartment 3 arranged forward of the piston against a discharge opening arranged at one container end wall, said material e.g. being grain, powder, granulate or material of (high) viscosity such as sludge. The sealing device is placed along the periphery of the piston and is formed with outwards directed ribs or cams 32 which are designed such that together with the interior wall of the cylindrical container they delimit one or more channels 31=31a, 31b, 31c, such that each channel has an outlet opening 38 at the forward side 3 of the piston 2, towards the discharge opening, and an inlet opening 36 at the rearward side of the piston 2, towards an opposing container end wall, in order to permit inflow of a fluid flow 35 through the inlet opening 36 and passage via the channel(s) 31=31a, 31b, 31c to an outflow 39 from the outlet opening 38 while carrying along and returning material pressed past the sealing cams 32, to the material compartment 3. <IMAGE> |
