Image forming apparatus and image forming method used in the apparatus

摘要

An image forming apparatus includes: a plurality of image forming units each with an image carrier on which an electrostatic latent image is formed, and each with a developing member for developing process on the electrostatic latent image, wherein the image forming apparatus superimposes toner images of the respective colors to form a composite color image; when images on a plurality of pages are formed, the developing members of the respective colors are started or stopped in response to presence or absence of latent images of the respective colors on a page that is targeted for image formation; and when the image forming unit starts to be driven, a developing member, corresponding to a color whose latent image is not to be formed on a first page of the plurality of pages, is not started.

主权项

1. An image forming apparatus comprising:
a plurality of image forming units, each of the image forming units including an image carrier on which an electrostatic latent image is formed, and each image forming unit includes a developing unit responsible for developing process on the electrostatic latent image formed on the image carrier, wherein with respect to a first image forming unit of the plurality of image forming units, a driving control of a developing unit for the first image forming unit is performed such that: (a) in the case where a second image forming unit of the plurality of image forming units performs image formation of a page while the first image forming unit does not perform image formation of the page, and then the first image forming unit performs image formation of a subsequent page, a developing unit of the first image forming unit starts to be driven at a time when the second image forming unit starts writing of a latent image of the page on an image carrier; (b) in the case where the first image forming unit performs image formation of a page, and then the first image forming unit does not perform image formation of a subsequent page, the developing unit being driven of the first image forming unit is stopped at a time when the second image forming unit starts writing of a latent image of the subsequent page on the image carrier; and (c) in the case where the drive start time and the drive stop time of the developing unit of the first image forming unit coincide with each at other, priority is given to the drive start time to start driving of the developing unit of the first image forming unit.