Image forming apparatus

Patent metadata

Field	Value
Publication number	US-2017357192-A1
Application number	US-201715687905-A
Country	US
Kind code	A1
Filing date	Aug 28, 2017
Priority date	Oct 10, 2013
Publication date	Dec 14, 2017
Grant date	—

Abstract

An image forming apparatus includes: an image carrying unit; a unit-to-be-moved; a pulse motor; a moving mechanism including a rotatable member provided with a member-to-be-detected; a detecting portion; an executing portion; and a controller for causing the executing portion to execute a first stop mode on the basis of detection of the detecting portion when the unit-to-be-moved is changed in position from the second or third position to the first position and to execute a second stop mode on the basis of a pulse number of a driving signal when the unit-to-be-moved is changed in position from the first or third position to the second position and when the unit-to-be-moved is changed in position from the first or second position to the third position, and for making the change at least between the second and third positions by only unidirectional rotation of the pulse motor.

First claim

1 - 8 . (canceled)

9 . An image forming apparatus comprising:
an image bearing member; a motor rotatable bi-directionally; a moving mechanism, including a cam rotated by said motor, capable of changing a position of a member-to-be-moved to three different positions relative to said image bearing member by switching a phase of said cam; a sensor configured to detect the phase of said cam; and a controller configured to control drive of said motor on the basis of a detection result of said sensor, wherein the three positions are a first position where the member-to-be-moved is disposed during image formation, a second position where the member-to-be-moved is disposed during the image formation and which is different from the first position, and a third position where the member-to-be-moved is not disposed during the image formation, wherein said sensor is capable of detecting the phase of said cam corresponding to the first position, and wherein said moving mechanism is configured to move the member-to-be-moved so that the member-to-be-moved reciprocates between the first position and the second position without passing through the third position.

10 . The image forming apparatus according to claim 9 , wherein when moving between the second position and the third position, said controller controls the drive of said motor so as to permit switching from the second position to the third position without passing through the first position and so as not to permit switching from the third position to the second position without passing through the first position.

11 . The image forming apparatus according to claim 9 , wherein when the image formation is carried out at the second position, said controller controls said motor so that the member-to-be-moved is disposed at the first position at an end of the image formation.

12 . The image forming apparatus according to claim 11 , wherein when the image formation is carried out in a state in which the position of the member-to-be-moved is switched from the first position to the second position, said controller controls said motor so that the position of the member-to-be-moved is switched from the first position to the second position without passing through the third position.

13 . The image forming apparatus according to claim 11 , wherein when the image formation is carried out in a state in which the member-to-be-moved is disposed at the third position, said image bearing member is detachably mountable to a main assembly of said image forming apparatus, and
wherein when the position of the member-to-be-moved is switched from the first position to the third position, said controller controls the drive of said motor so that the position of the member-to-be-moved is switched from the first position to the third position via the second position.

14 . The image forming apparatus according to claim 9 , wherein the member-to-be-moved is movable toward and away from said image bearing member and includes first and second transfer members each configured to transfer an image onto said image bearing member,
wherein said first transfer member contacts said image bearing member when the member-to-be-moved is disposed at the first position and at the second position, and is spaced from said image bearing member when the member-to-be-moved is disposed at the third position, and wherein said second transfer member contacts said image bearing member when the member-to-be-moved is disposed at the third position, and is spaced from said image bearing member when the member-to-be-moved is disposed at the first position and at the second position.

15 . The image forming apparatus according to claim 9 , wherein the member-to-be-moved is movable toward and away from said image bearing member and includes a transfer member configured to transfer an image onto said image bearing member,
wherein when the member-to-be-moved is disposed at the first position, said transfer member contacts said image bearing member, wherein when the member-to-be-moved is disposed at the second position, said transfer member is disposed at a first spaced position where said transfer member is spaced from said image bearing member, and wherein when the member-to-be-moved is disposed at the first position, said transfer member is disposed at a second spaced position longer in spaced distance between said transfer member and said image bearing member than the first spaced position.

16 . The image forming apparatus according to claim 15 , wherein when a reference pattern, which is not to be transferred onto a recording material during the image formation, is formed, said controller controls the drive of said motor so that the position of the member-to-be-moved is switched from the first position to the second position.

Assignees

• Canon Kk

Inventors

• Tajiri Tsuyoshi

Classifications

• G03G15/50 Primary

  Machine control of apparatus for electrographic processes using a charge pattern, e.g. regulating differents parts of the machine, multimode copiers, microprocessor control (sequencing control G03G21/14) · CPC title

• G03G15/1615 Primary

  relating to the driving mechanism for the intermediate support, e.g. gears, couplings, belt tensioning · CPC title

• G03G15/01

  for producing multicoloured copies · CPC title