Paper separation and feed mechanism utilizing electrostatic force

A new paper separation and feed mechanism is proposed to realize a highly reliable paper handling system for printers. A prototype mechanism consisted of a plate or roller separation electrode coated with an insulated film, a ground electrode, and a paper pile between the electrodes. When high voltage was applied between the electrodes, charge was excited on the insulating film and eletrostatic force is applied to the paper. Electrostatic separation of a sheet of paper was realized at the top of the pile when the applied voltage exceeded a threshold voltage to generate electrostatic force large than the weight of a sheet of paper. The threshold voltage was about some kV, and it agreed with the numerical value obtained by the FEM calculations for the electrostatic field. In the next step the roller electrode was rotated to feed the attached paper. However the applied voltage had to be increased to separate subsequent papers, because charge on the insulated film was cancelled by the attached paper. Then a biased charger roller was settled in contact with the roller electrode to charge the insulating film on the roller separation electrode. In this system, reliable paper separation and feed was realized and a feed speed over 600 mm/s was demonstrated.