Abstract: A pneumatically powered toner delivery system for a hard copy machine is disclosed which is particularly adaptable to color printing and plotting in which liquid toner is used to produce electrophotographic images. A diaphragm pump is connected by a controllable rotary valve (or a manifold) to each toner reservoir of the system. Pneumatic pressure is selectively applied to the cartridges. The cartridges are connected to respective developer subsystems where toner of a particular color under pneumatic pressure from a reservoir is delivered to a developer subsystem for transfer to a photoconductor bearing a latent image.

Abstract: Airflow is used to substantially eliminate problems cause by excess liquid toner flow in developing a latent image on a photoconductor surface. Edge effects at each end of a squeegee roller are prevented by concentrating an airstream at the nip interface of the squeegee roller with the photoconductor. Drip lines are prevented by providing a laminar airflow across the squeegee roller interface with the photoconductor to force excess toner away from the nip interface before the excess liquid can pass through the nip and cause a drip line.

Abstract: A cartridge for dispensing metered amounts of liquid electrophotography toner concentrate. The cartridge comprises first and second endcaps within a hollow of the cartridge for confining the concentrate; a tube rigidly attached to the first endcap having a passage therein for allowing expulsion of the concentrate when pressure is applied to the concentrate by the first endcap; and a first and second control lip rigidly attached to the tube for metering the expulsion of concentrate out through the passage. In an alternate embodiment, the first endcap is a diaphragm whereby the bowing capacity of the diaphragm meters a controlled amount of concentrate out through the passage. A pressurized medium or vacuum acts upon the first endcap to effectuate a pumping of the concentrate out through the passage for mixing with a carrier fluid.

Abstract: An EP printer include a photoconductor-coated drum which has, at its respective ends, a pair of cam plates. Each of the cam plates is provided with plural cam paths, at least a pair of which are employed to control both squeegee and developer rollers within adjacently positioned plural color toner developer modules. A pair of additional cam paths on the cam plates, in combination with link arms and spring-biased follower mechanisms, enable selective engagement and disengagement of a transfer roller with the photoconductor surface so as to enable transfer of a toned image to a media sheet.

Abstract: In an electrophotographic printer, an apparatus for supplying a liquid toner that has a solids concentration within a predefined range. A concentrated solids material and a carrier liquid is contained within a reservoir. The concentrated solids has a solids concentration higher than the predefined range and has settled out from the carrier liquid. A tube has its orifice submerged in the concentrated solids material A second tube has its orifice submerged in the carrier liquid. To insure that the second tube remains above the concentrated solids material and simultaneously below the upper surface, a float is formed around the tube. Finally, a mixer is connected to the two tubes and mixes the concentrated solids with carrier liquid to create the liquid toner. The solids concentration range is directly related to the rations of the two orifices.