JP2010139778A5 - - Google Patents

Description

The above object is achieved by the image forming apparatus according to the present invention. In summary, the first aspect of the present invention includes a photosensitive member, a charging member for charging said photosensitive member, said the indicia pressurizing means you apply a voltage to the charging member, the photosensitive member charged by the charging member and shape forming means that form a picture, said a transportable Okukarada you carrying the image transferred from the photosensitive member, a front Symbol photoreceptor before Ki搬 Okukarada make contact spacing the mechanism, before Symbol charging member wherein the detecting means that detect a current that flows, when starting the image forming processing, when applying a predetermined voltage to the charging member by said applying means while rotating the said photosensitive member spaced apart from the carrier When the current detected by the detecting means is within a predetermined range, the photosensitive member by the mechanism is allowed to contact the transporting body, and when the current is outside the predetermined range, the photosensitive member by the mechanism and the Stop the image forming process without contacting the carrier And control means for controlling such a images forming apparatus that have a.

According to the second aspect of the present invention, the first image forming section that includes the first photoconductor and forms an image on the first photoconductor, the second photoconductor, and the charging member that charges the second photoconductor A second image forming unit that forms an image on the second photosensitive member, an application unit that applies a voltage to the charging member, a detection unit that detects a current flowing through the charging member, and the first photosensitive member. An intermediate transfer member that conveys an image formed on the body and an image formed on the second photosensitive member to a position where the image is transferred to a recording material, and the intermediate transfer member that contacts only the first photosensitive member. A posture, a mechanism that can be switched to a second posture in contact with the first photosensitive member and the second photosensitive member, and the intermediate transfer member and the first photosensitive member when the mechanism is switched from the first posture to the second posture. And rotating the second photosensitive member separated from the intermediate transfer member. When the current detected by the detection means is within a predetermined range when a predetermined voltage is applied to the charging member by the applying means, the second photoconductor and the intermediate transfer body are moved at a predetermined speed. There is provided an image forming apparatus comprising: a control unit that switches the mechanism to the second posture while rotating .

When the intermediate transfer belt 91 is separated from the photosensitive drum 1, the contact / separation mechanism 14 moves the tension roller 95 by a predetermined amount h by the moving unit 15 (FIG. 2 : first posture ). At this time, the abutment / separation mechanism 14 operates in conjunction with the tension roller 95, so that the first to third image forming units PY, PM, and PC (second image forming unit) perform first to third. The primary transfer rollers 92Y, 92M, and 92C are separated from the first to third photosensitive drums 1Y, 1M, and 1C (second photosensitive member) . At this time, in the fourth image forming unit PBk (first image forming unit) , the intermediate transfer belt 91 is not separated from the photosensitive drum 1Bk (first photosensitive member) . Therefore, even if the contact / separation mechanism 14 is moved by the transfer position maintaining roller 110 provided on the back side of the intermediate transfer belt 91 between the third image forming unit PC and the fourth image forming unit PBk. The position of the primary transfer roller 92Bk No. 4 is hardly changed. Further, when the intermediate transfer belt 91 is brought into contact with the photosensitive drum 1, the tension roller 95 is moved by the moving unit 15 in the opposite direction to the case where it is separated from the above. As a result, the contact / separation mechanism 14 operates in conjunction with the tension roller 95 to direct the first to third primary transfer rollers 92Y, 92M, and 92C toward the first to third photosensitive drums 1Y, 1M, and 1C. And pressurize (FIG. 1 : second posture ).

Claims (5)

A photoreceptor,
A charging member for charging the photoreceptor;
And indicia pressurizing means you apply a voltage to said charging member,
And shape forming means that form a picture on the photosensitive member charged by the charging member,
A transportable Okukarada you conveying the image transferred from the photosensitive body,
A mechanism for causing contact spaced a pre Symbol photoreceptor before Ki搬 Okukarada,
A detecting means that detect a current flowing before Symbol charging member,
When starting the image forming process, the current detected by the detection means when the photosensitive member separated from the transport body is driven to rotate and a predetermined voltage is applied to the charging member by the applying means is within a predetermined range. In this case, it is allowed to bring the photosensitive member and the conveying member into contact with each other, and when it is outside a predetermined range, the image forming process can be performed without bringing the photosensitive member and the conveying member into contact with each other. Control means for controlling to stop ;
Images forming apparatus that have a. Before Ki搬 Okukarada image forming apparatus according to claim 1, characterized in that an intermediate transfer member for conveying to the position for transferring the image transferred from the photosensitive member to the recording material. Wherein, when the image forming processing is completed, the image forming apparatus according to claim 1 or 2, characterized in that to control the so that is separated the photosensitive member and the front Ki搬 Okukarada by the mechanism .   A first image forming unit comprising a first photoconductor, and forming an image on the first photoconductor;
  A second image forming section for forming an image on the second photoconductor, comprising: a second photoconductor; and a charging member for charging the second photoconductor;
  Applying means for applying a voltage to the charging member;
  Detecting means for detecting a current flowing through the charging member;
  An intermediate transfer member that conveys the image formed on the first photosensitive member and the image formed on the second photosensitive member to a position where the image is transferred to a recording material;
  A mechanism capable of switching between a first posture in which the intermediate transfer member contacts only the first photosensitive member and a second posture in contact with the first and second photosensitive members;
  When the mechanism is switched from the first posture to the second posture, the intermediate transfer member and the first photosensitive member are rotated, and the second photosensitive member separated from the intermediate transfer member is driven to rotate. When the current detected by the detecting means when a predetermined voltage is applied to the charging member is within a predetermined range, the mechanism is operated while rotating the second photosensitive member and the intermediate transfer member at a predetermined speed. Control means for switching to the second posture;
An image forming apparatus comprising:   The image forming apparatus according to claim 4, wherein the control unit controls the mechanism to assume a first posture when the image forming process is completed.