Electrographic recording devices employing electrostatic induction electrodes

An electrostatic recording device comprising:

• a plurality of groups of record electrodes, corresponding record electrodes in each group being connected in common;
• a plurality of impedance elements each of which is connected with each of the commonly connected record electrodes;
• a plurality of first high-voltage switching circuits connected with the commonly connected record electrodes via the respective impedance elements;
• a plurality of electrostatic induction plates, the number of which corresponds to the number of the groups of the record electrodes, said electrostatic induction plates being disposed adjacent each of the record electrode groups or their associated lead wire portions and capacitively coupled thereto via insulation means;
• and
• a plurality of second high-voltage switching circuits connected with the induction plates.

An electrostatic recording device comprising a recording head carrying a multiplicity of record electrodes and a record medium on which a charge pattern is disposed by virtue of discharge on the record electrodes, said recording device comprising:

• means for dividing the multiplicity of the record electrodes into a predetermined number of groups;
• first high-voltage switching circuits divided into a predetermined number of groups, the adjacent groups of the record electrodes being operatively associated with the different groups of the first high-voltage switching circuits, respectively;
• circuit means for connecting the thus associated record electrodes and switching circuits;
• a plurality of electrostatic induction plates provided for each of the groups of the record electrodes said induction plates being capacitively coupled to said record electrode via insulation means;
• and
• second high-voltage switching circuits connected with the respective electrostatic induction plates.