| 摘要 |
<p>A system for separating one surface, preferably a web, from another surface, to enable a bead of accumulated material, e.g. comprising a liquid or solid particles, built up at the line of contact between the two surfaces to pass therebetween. In the preferred embodiments, the accumulated material bead bypass system is employed in photoelectrophoretic imaging to bypass a bead of imaging suspension and also to serve as a web stabilizer and control device. In a particular embodiment, the bead bypass system includes two rollers adjacent to, and on either side of, the imaging roller in the imaging zone. The two rollers provide a web path, web stability and determine the imaging nip. When a significant build-up of liquid takes place to form a bead at the line of contact between the web and the imaging roller by reason of the web advancing relative thereto, at least one of either a single roller, both rollers or the imaging roller is cammed from the imaging mode thereby sharply separating the web from the imaging roller, allowing the excess liquid bead to pass thereby beyond the imaging area between image frames, to inter alia, remove the effect of the bead on the next frame of web to be imaged.</p> |
