Method and apparatus for de-aerating viscous mixing stock
AssigneeDraiswerke GmbH
InventorHerbert Duerr
Life of this patent
Estimating the term…
Abstract
A de-aerating agitating mill, especially for paints, pigments and the like in which the mixing chamber is closed off from a discharge chamber which may be subjected to reduced pressure. The closure is effected by a separator device consisting of a central disk which is attached to the stirrer or agitator shaft and rotates in a hole within a stationary part of the casing. A narrow, annular gap between the periphery of the disk and the rim of the hole acts as an outlet channel through which the ground or mixed stock is extruded. The shear stresses exerted on the stock rupture the material and burst any air bubbles which are then removed by the vacuum.
Claims12
A method for de-aerating viscous stock, especially pasty paint, comprising the steps of:
- grinding said stock in a grinding chamber where said stock is not subject to vacuum pressure;
- providing an exit slot for said stock from said grinding chamber into a discharge chamber,
- providing vacuum pressure in said discharge chamber, and
- configuring said exit slot such that it prevents the vacuum pressure from entering said grinding chamber;
- said slot forming said stock into a layer as it exits said grinding chamber;
- it said slot being defined by a pair of surfaces and progressively increasing in traverse width moving from said grinding chamber to said discharge chamber;
- about an axis moving at least one of said surfaces during grinding and said surfaces are both inclined radially outwardly of said axis of said motion of said slot defining surfaces.
A closed agitating mill, comprising a cylindrical container for grinding stock, said cylindrical container surrounding a grinding chamber;
- means for supplying stock to said grinding chamber;
- a rotatably drivable agitator disposed in said grinding chamber;
- a separator device disposed in said container between said grinding chamber and a discharge chamber, said separator device including an exit slot through which said stock is forced from said grinding chamber, means to provide vacuum in said discharge chamber, and said slot being so configured that it prevents the vacuum pressure from entering said grinding chamber;
- said slot forming said stock into a layer as it exits said grinding chamber;
- said slot being relatively elongated between said chambers and progressively increasing in traverse width moving from said grinding chamber to said discharge chamber;
- said slot being defined by a pair of surfaces at least one of which moves with respect to the other about an axis;
- and said surfaces are both inclined radially outwardly of said axis of said relative motion of said slot defining surfaces.
Dependencies are inferred from the claim text.