| 摘要 |
A spacing mechanism is provided to vary the distance between a rotary platen and a pagewidth printhead as a function of the angle of rotation of the platen. The spacing mechanism includes cams fixed at opposing ends of the platen and corresponding cam followers mounted fast with the printhead and positioned to follow the cams. Springs are arranged to bias the cam followers against the cams in use. The platen includes a number of radially located elongate working surfaces each providing a servicing function to the printhead that requires a different platen-to-printhead spacing. The cams are shaped to suitably vary the printhead-to-platen distance between each working surface and the printhead as the working surface is rotated adjacent to the printhead. |
