Traveling electrostatic waves rather than mechanical systems can be used to transport charged toner particles as a controlled aerosol. Extensive theoretical and experimental work on this subject has been done by Masuda, Schmidlin and Melcher et al. These authors used experimental setups with electrodes arranged in a grid structure. Multiple phase shifted sinusoidal voltages were applied to the groups of these electrodes to generate a traveling electrostatic wave.As an alternative to using sinusoidal voltages, we propose a new method. Charged toner particles are transported utilizing the bucket brigade principle as it is used in charged-coupled devices (CCD).For experimental work, a programmable 4-channel high voltage multiplexer has been developed which is able to switch voltages up to 1500 V. A traveling electrostatic wave suitable for toner transport is generated by multiplexing the voltages applied to groups of electrodes in an appropriate manner.In first promising experiments using a Masuda panel, particle transport was achieved with conductive, magnetic monocomponent toner. At low switching frequencies, the charged toner particles moved synchronously in the direction of the traveling wave. A critical frequency was found at which propagation in both directions appeared and above this frequency backwards transport was observed.
Ralph Kober, Bernhard Hill, "An Experimental Setup for Bucket Brigade Toner Transport" in Proc. IS&T Int'l Conf. on Digital Printing Technologies (NIP15), 1999, pp 258 - 261, https://doi.org/10.2352/ISSN.2169-4451.1999.15.1.art00067_1