US 8,620,185 B2 · Image forming apparatus featuring phase relationship adjustment between image bearing members

Abstract

A phase synchronization mode is performed at a time of subsequent rotation after image formation. After detection of a phase difference by phase detecting sensors 103a, 103d, rotation phases are synchronized between driving motors 111, 102d after a lapse of a variable time. Specifically, timing for starting the rotation phase synchronization is shifted by 20 msec for each phase synchronization control so as to vary angular positions of the photosensitive drums 101a, 101b, 101d at which phase control is started. In this manner, sliding-contact positions are distributed and development and concentration of sliding-contact damages are prevented on the photosensitive drums 101a, 101b, 101d.

Drawings

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Drawings

Claims11

Dependent claims

An image forming apparatus comprising:

a first image bearing member;
a second image bearing member;
a rotating member which is rotated by coming in contact with the first image bearing member and the second image bearing member;
a first driving motor which transmits a driving force to the first image bearing member;
a second driving motor which transmits a driving force to the second image bearing member;
a detecting unit which performs a detection of a phase relationship of rotation of the first image bearing member with respect to rotation of the second image bearing member;
an adjusting unit which performs an adjustment of a traveling speed subsequently to the detection of the phase relationship, and performs an adjustment of the phase relationship by changing a traveling speed of at least one image bearing member of the first image bearing member and the second image bearing member so as to set the phase relationship to a predetermined phase relationship;
and
a changing unit which changes a predetermined time from a start of the detection of the phase relationship by the detecting unit to a start of the adjustment of the traveling speed of the at least one image bearing member.

6 more elements

Dependencies are inferred from the claim text.

Description7,320 words

Summary911 words

#1. Field of the Invention

#The present invention relates to an image forming apparatus having a plurality of image bearing members disposed along an intermediate transfer member or a recording material conveying member, and more particularly to control of adjusting a rotation phase positions between the two image bearing members with different driving motors.

#2. Description of the Related Art

Brief description of the drawings10 figures

#FIG. 1 is a view illustrating a configuration of an image forming apparatus.

#FIG. 2 is a view illustrating a configuration of an image forming portion for yellow.

#FIGS. 3A and 3B are views illustrating rotation variations of photosensitive drums.

Detailed description6,261 words

#In the following, embodiments of the present invention will be described in detail manner with reference to the drawings. As long as every phase synchronization control is performed at positions distributed on the periphery of the photosensitive drums, the present invention can be carried out with another embodiment achieved by replacing part or all of this embodiment with an alternative configuration.

#Therefore, with any tandem type provided with two or more image bearing members, regardless of a developing system, a charging system, or an electrostatic image forming system, and regardless of the number of image forming portions, the present invention can be carried out regardless of an intermediate transfer system or a recording material conveying system.

#This embodiment describes only the essential parts which are related to formation and transfer of a toner image. However, the present invention may be carried out for various applications such as a printer, various printing machines, a copying machine, and a fax machine, by adding necessary devices, equipment, and a housing configuration.

Facts

Application

12/948,998Filed 18 Nov 2010

Priority

JP 2009-2731881 Dec 2009

Published

US 2011/0129255 A12 Jun 2011

Granted

31 Dec 2013

Term ends

9 Jan 2031

Estimated · how

20 years from earliest known nonprovisional domestic filing plus recorded patent term adjustment, including 52 days of adjustment. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification5 codes

G03G 15/5008
Machine control of apparatus for electrographic processes using a charge pattern, e.g. regulating differents parts of the machine, multimode…:…
G03G 15/0194
Using more than one reusable electrographic recording member, e.g. one for every monocolour image: primary transfer to the final recording medium
G03G 2215/0129
The linear arrangement being horizontal or slanted: horizontal medium transport path at the secondary transfer
G03G 2215/0158
Characterised by the technical problem: colour registration

Timeline

1 Dec 2009Priority claimedJP 2009-273188
18 Nov 2010Application filedUS 12/948,998
22 Mar 2011Assigned to Canon Kabushiki Kaishaassignment of assignor's interest
2 Jun 2011PublishedUS 2011/0129255 A1
31 Dec 2013GrantedUS 8,620,185 B2
12 Oct 2026TodayWithin its term
9 Jan 2031Term endsEstimated, includes 52 days of adjustment

Image forming apparatus featuring phase relationship adjustment between image bearing members

Life of this patent

Image forming apparatus featuring phase relationship adjustment between image bearing members

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims11

Description7,320 words

Drawings

Classification5 codes

Life of this patent

Description7,320 words