| 摘要 |
An electrostatographic single-pass multiple station multi-colour printer for forming an image onto a web (12), eg of paper, is described. The printer comprises a plurality of toner image-producing electrostatographic printing stations (A, B, C, D, E) each having rotatable endless surface means (26) such as the photoconductive surface of a cylindrical drum (24) onto which a toner image can be formed. The paper web (12) is conveyed in succession past the printing stations (A, B, C, D, E). The speed and tension of the web (12) is controlled while it is running past the printing stations (A, B, C, D, E). Guiding rollers (36) which determine for the web (12) wrapping angles ( omega ) of about 15 DEG about the drum surface. A corona device transfers the toner image on each drum onto the web (12). The corona device, the wrapping angles omega and the web tension are such that adherent contact of the web (12) with the drum surface (26) is such that the moving paper web (12) controls the peripheral speed of the drum in synchronism with the movement of said web. Slippage between the drum surface (26) and the paper web (12) is thereby eliminated, enabling accurate registration of superimposed images on the paper web (12). <IMAGE> |
