Measuring and monitored neutralising of surface charges on objects, e.g. paper or plastic foil - using charge neutralising brush whose position is varied according to measured charge

摘要

The method involves using a charge neutralising brush (5) of thin electrically conducting wires. The quantity of charge on the object (1) surface is measured with a charge sensor (2). The discharge current flowing via the neutralising brush is measured and both measurement parameters fed into a microprocessor (11) which determines the already compensated charge and the residual charge. The charges are compared to produce a control signal which is used to control the distance of the brush from the surface of the object by means of an electromechanical positioning mechanism (7). Complete compensation of the charge is achieved during the transition time of the object. USE/ADVANTAGE - E.g. for measuring and neutralising charge on surface of paper or plastic foil. Method enables definite discharge to be caused independent of charge state, material properties and thickness of object.