Abstract: Systems and techniques are described relating to a filter assembly. In one embodiment, an ink filter assembly includes an inlet channel configured to direct a flow of ink toward an elongated chamber, and an outlet channel configured to direct the flow of ink from an elongated chamber to an ink nozzle assembly. An elongated chamber extends from the inlet channel to the outlet channel, and a membrane provides a permeable separator between an upper section of the elongated chamber and a lower section of the elongated chamber. The membrane is orientated approximately parallel to a longitudinal axis of the elongated chamber and the flow of ink passes through the membrane.

Abstract: A retractable writing instrument that substantially prevents writing fluid from evaporating through the tip when the tip is in a retracted position to eliminate the need for a cap. Within the writing instrument is an enclosure member that has a vapor chamber. In the retracted position, the tip of the writing instrument is within the vapor chamber to substantially seal the tip from ambient air so that writing fluid does not evaporate through the tip. The enclosure member has a lip that opens to allow the tip to move forward and extend from the writing instrument so that writing fluid can be delivered to the writing surface for writing. When the tip is moved back into the retracted position the lip closes to substantially seal the tip from the ambient air. An external compression force may be applied to the lip to assist in sealing the lip.

Abstract: This invention provides a retractable writing instrument that substantially prevents writing fluid from evaporating through the tip when the tip is in a retracted position to eliminate the need for a cap. Within the writing instrument is an enclosure member that has a vapor chamber. In the retracted position, the tip of the writing instrument is within the vapor chamber to substantially seal the tip from ambient air so that writing fluid does not evaporate through the tip. The enclosure member has a lip that opens to allow the tip to move forward and extend from the writing instrument so that writing fluid can be delivered to the writing surface for writing. When the tip is moved back into the retracted position the lip closes to substantially seal the tip from the ambient air. An external compression force may be applied to the lip to assist in sealing the lip.

Abstract: An improved toner applying apparatus is provided for developing an electrographic latent image formed on the charge retaining surface of a moving recording medium. The toner applicator includes a housing defining an internal reservoir and including a series of longitudinal, parallel toner applying recesses which are disposed for developmental engagement with a moving recording medium across its entire width. Each toner applying recess communicates with the reservoir. Internal baffles are provided across a toner inlet to the reservoir chamber to provide uniform fluid pressure throughout the reservoir. The parallel toner applying recesses provide a more even and constant flow of toner than is possible in prior art roller applicators and completely eliminate the problem of electrodeposition or plating up of toner particles on the applicator.