US 4,879,137 A · Method and apparatus for electrostatic coating with conductive material

Abstract

In an apparatus for electrostatically coating workpieces with an electrically conductive coating material, an intermediate isolation tank (V) is conencted by electrically insulating conduit lines (LVA, LVB, LZA, LZB) between an electrically grounded coating material supply and a high voltage spraying device atomizer (Z). When the apparatus is in operation, the conduit lines (LVA, LVB, LZA, LZB) are alternately filled and emptied, such that the grounded supply and the high voltage atomizer (Z) are continuously insulated from each other. One embodiment utilizes an isolation tank V' which includes a metering cylinder (DZ) having a displaceable piston (2) for adjusting the coating material capacity of the tank (V') to the amount required to coat a single workpiece.

Claims10

Dependent claims

A method for successively coating workpieces with an electrically conductive coating material comprising the steps of:

moving a quantity of coating material from a storage supply to an intermediate isolation tank (V');
moving the quantity of coating material from the isolation tank (V') to a spraying device (Z) for coating a workpiece;
and characterized by adjusting the capacity of the isolation tank (V') prior to moving the coating material to the tank to correspond with the quantity of coating material to be supplied from the storage supply and moved to the spraying device (Z).

A coating apparatus for successively coating workpieces with an electrically conductive coating material comprising:

an isolation tank (DZ) having a coating material capacity for storing coating material supplied thereto;
a spraying device (Z) in fluid communication with said isolation tank (V') for spraying coating material from said isolation tank (V') onto a workpiece;
fluid expulsion means (PL.sub.1) associated with said isolation tank (V') for applying a pressurized gas to the coating material in said isolation tank (V') to move the coating material from said location tank (V') to said spraying device (Z);
and said isolation tank (V') including metering cylinder means (DZ) for adjusting the coating material capacity of said isolation tank (DZ) to a predetermined volume before coating material is supplied thereto and for maintaining the capacity at the predetermined volume while said fluid expulsion means (PL.sub.1) moves the coating material therefrom.

1 more element

Dependencies are inferred from the claim text.

Method and apparatus for electrostatic coating with conductive material

Life of this patent

Method and apparatus for electrostatic coating with conductive material

Life of this patent

Abstract

Claims10