Abstract: An image forming apparatus includes: an image bearing member for bearing a toner image; a belt for conveying the toner image; and a transfer device for rubbing the belt, and a surface of the transfer device, which is brought into contact with the belt includes linear concave portions or linear convex portions. The image forming apparatus of the present invention prevents a friction force between the belt and the transfer device rubbing the belt from increasing and brings a transfer member into a stable contact with the belt for conveying the toner image, thereby suppressing increase in drive torque of the belt which rubs the transfer device and suppressing occurrence of image failure.

Abstract: An image forming apparatus includes: an image bearing member for bearing a toner image; a belt for conveying the toner image; and a transfer device for rubbing the belt, and a surface of the transfer device, which is brought into contact with the belt includes linear concave portions or linear convex portions. The image forming apparatus of the present invention prevents a friction force between the belt and the transfer device rubbing the belt from increasing and brings a transfer member into a stable contact with the belt for conveying the toner image, thereby suppressing increase in drive torque of the belt which rubs the transfer device and suppressing occurrence of image failure.

Abstract: An image forming apparatus for forming image on a recording medium includes a photosensitive member, a motor, a belt, and a drive member to rotate the belt, the drive member including a driven coupling. The apparatus also includes a drive coupling to rotate by a driving force generated by the motor, the drive coupling being movable in an axial direction to take an engagement position at which the driving force is transmittable to the driven coupling, and a release position. The apparatus further includes a transfer member to transfer a toner image onto the recording medium or the belt, a voltage application unit to apply a voltage to the transfer member, and a control unit to cause the voltage application unit to apply the voltage to the transfer member after the drive coupling moves to the engagement position and the driving force is transmitted to the driven coupling.

Abstract: A fixing roller has a base layer, a rubber layer formed on the base layer and a surface layer formed of a fluororesin tube, and a heater disposed inside the roller. The surface layer of the roller is formed by covering the fluororesin tube on the rubber layer in a condition where the fluororesin tube is pulled in a radial direction of the fluororesin tube, the fluororesin tube has an internal diameter less than an outer diameter of the roller and a thickness of 20 microns or smaller and a crystallization degree of the fluororesin tube being 50% or smaller. The roller is made by expanding the fluororesin tube is in a radial direction and drawing the fluororesin tube in a generatrix direction thereof, wherein a drawing ratio of the fluororesin tube in the drawing the fluororesin tube in the generatrix direction is 5% or smaller.

Abstract: An image forming apparatus for forming image on a recording medium includes a photosensitive member, a motor, a belt, and a drive member to rotate the belt, the drive member including a driven coupling. The apparatus also includes a drive coupling to rotate by a driving force generated by the motor, the drive coupling being movable in an axial direction to take an engagement position at which the driving force is transmittable to the driven coupling, and a release position. The apparatus further includes a transfer member to transfer a toner image onto the recording medium or the belt, a voltage application unit to apply a voltage to the transfer member, and a control unit to cause the voltage application unit to apply the voltage to the transfer member after the drive coupling moves to the engagement position and the driving force is transmitted to the driven coupling.

Abstract: There is a charge member which charges secondary transfer remaining toner on an intermediate transfer member to a polarity opposite to a normal charge polarity. The transfer remaining toner charged by the charge member is moved in the direction opposite to that of normal toner by a transfer bias and moved from the intermediate transfer member onto an image bearing member. A BK station is arranged on the downstream of other stations. In a continuous BK monochromatic mode, by applying a reverse bias to transfer portions of the other stations and applying the transfer bias only to the BK station, waste toner can be collected into the BK station (simultaneously with the transfer). In a full-color mode, since each transfer bias is applied to all stations, the waste toner is collected into the station on the uppermost stream.

Abstract: An image forming apparatus includes an image bearing member for bearing a toner image; a rotatable intermediary transfer member; and a transfer unit, configured and positioned to form a transfer nip between the intermediary transfer member and the image bearing member, for transferring the toner image from the image bearing member onto a surface of the intermediary transfer member. The transfer unit includes a sheet member on which the intermediary transfer member is slidable, and includes an elastic member for urging the sheet member toward the intermediary transfer member at a position of the transfer nip. The sheet member is provided with a reinforcing portion, having a linear expansion coefficient different from that of the sheet member, in an area in which the elastic member urges the sheet member.

Abstract: An image forming apparatus includes an image bearing member for bearing a toner image; an endless rotatable intermediary transfer belt onto which the toner image is to be transferred from the image bearing member; a transfer device disposed at a position in which the transfer device opposes the image bearing member through the intermediary transfer belt, the transfer device including a sheet member surface-contacted to an inner surface of the intermediary transfer belt and including an urging member for urging the sheet member toward the intermediary transfer belt; and a primary transfer voltage source for applying a voltage to the sheet member.

Abstract: There is a charge member which charges secondary transfer remaining toner on an intermediate transfer member to a polarity opposite to a normal charge polarity. The transfer remaining toner charged by the charge member is moved in the direction opposite to that of normal toner by a transfer bias and moved from the intermediate transfer member onto an image bearing member. A BK station is arranged on the downstream of other stations. In a continuous BK monochromatic mode, by applying a reverse bias to transfer portions of the other stations and applying the transfer bias only to the BK station, waste toner can be collected into the BK station (simultaneously with the transfer). In a full-color mode, since each transfer bias is applied to all stations, the waste toner is collected into the station on the uppermost stream.

Abstract: An image forming apparatus includes an image bearing member for bearing a toner image; a rotatable intermediary transfer member; and a transfer unit, configured and positioned to form a transfer nip between the intermediary transfer member and the image bearing member, for transferring the toner image from the image bearing member onto a surface of the intermediary transfer member. The transfer unit includes a sheet member on which the intermediary transfer member is slidable, and includes an elastic member for urging the sheet member toward the intermediary transfer member at a position of the transfer nip. The sheet member is provided with a reinforcing portion, having a linear expansion coefficient different from that of the sheet member, in an area in which the elastic member urges the sheet member.

Abstract: An image forming apparatus for forming image on a recording medium includes a photosensitive member, a motor, a belt, and a drive member to rotate the belt, the drive member including a driven coupling. The apparatus also includes a drive coupling to rotate by a driving force generated by the motor, the drive coupling being movable in an axial direction to take an engagement position at which the driving force is transmittable to the driven coupling, and a release position. The apparatus further includes a transfer member to transfer a toner image onto the recording medium or the belt, a voltage application unit to apply a voltage to the transfer member, and a control unit to cause the voltage application unit to apply the voltage to the transfer member after the drive coupling moves to the engagement position and the driving force is transmitted to the driven coupling.

Abstract: An apparatus includes an image bearing member for carrying an image; an intermediary transfer member for receiving the image; a primary transfer member for transfer of the image onto the intermediary transfer member in a primary transfer station; a secondary transfer member for transfer of the image onto a transfer material in a secondary transfer station; a first charging member for charging toner remaining in a region upstream of the primary transfer station and downstream of the secondary transfer station; and a second charging member for charging the toner remaining in a region upstream of the primary transfer station and downstream of the first charging member. The first charging member rubs a surface of, and the second charging member moves in contact with, the intermediary transfer member, to transfer the toner remaining on the intermediary transfer member to the image bearing member simultaneously with the primary transfer.

Abstract: An image forming apparatus comprises an image forming part and a density calibration control part. The image forming part forms an image in any one of a plurality of image forming modes with respectively different processing speeds. The density calibration control part performs image density control for the image forming part in a state where any one of the plurality of image forming modes is applied. Herein, the density calibration control part makes a performing time interval for the image density control in a first image forming mode and a performing time interval for the image density control in a second image forming mode different from each other.

Abstract: An image forming apparatus includes: an image bearing member for bearing a toner image; a belt for conveying the toner image; and a transfer device for rubbing the belt, and a surface of the transfer device, which is brought into contact with the belt includes linear concave portions or linear convex portions. The image forming apparatus of the present invention prevents a friction force between the belt and the transfer device rubbing the belt from increasing and brings a transfer member into a stable contact with the belt for conveying the toner image, thereby suppressing increase in drive torque of the belt which rubs the transfer device and suppressing occurrence of image failure.

Abstract: A fixing apparatus, a roller for a fixing apparatus, and a flexible sleeve for a fixing apparatus are a roller for the fixing apparatus (1) having a rubber layer (1b) and a fluororesin tube as a surface layer (1c) covered thereon. A thickness of the fluororesin tube is 20 microns or smaller, and a crystallization degree of the fluororesin tube is 50% or smaller. Thus, in the roller for the fixing apparatus having the rubber layer on which the resin tube is covered as the surface layer, a crack does not occur in the fluororesin tube even if the fluororesin tube is made thin.

Abstract: A developing apparatus includes a developer carrying member, disposed opposite to an image bearing member, for carrying developer which is caused to jump from the developer carrying member to the image bearing member to develop an electrostatic latent image formed on said image bearing member by creating an oscillation electric field between the image bearing member and the developer carrying member at an opposing portion where the image bearing member and the developer carrying member are opposed to each other; and a jumping developer regulation member for regulating an area in which the developer is caused to jump in the opposing portion. The jumping developer regulation member is disposed apart from the developer carried by the developer carrying member and is an insulating member or an electrically floating member.

Abstract: There is a charge member which charges secondary transfer remaining toner on an intermediate transfer member to a polarity opposite to a normal charge polarity. The transfer remaining toner charged by the charge member is moved in the direction opposite to that of normal toner by a transfer bias and moved from the intermediate transfer member onto an image bearing member. A BK station is arranged on the downstream of other stations. In a continuous BK monochromatic mode, by applying a reverse bias to transfer portions of the other stations and applying the transfer bias only to the BK station, waste toner can be collected into the BK station (simultaneously with the transfer). In a full-color mode, since each transfer bias is applied to all stations, the waste toner is collected into the station on the uppermost stream.

Abstract: An image forming apparatus comprises an image forming part and a density calibration control part. The image forming part forms an image in any one of a plurality of image forming modes with respectively different processing speeds. The density calibration control part performs image density control for the image forming part in a state where any one of the plurality of image forming modes is applied. Herein, the density calibration control part makes a performing time interval for the image density control in a first image forming mode and a performing time interval for the image density control in a second image forming mode different from each other.

Abstract: An image forming apparatus includes a plurality of image forming parts, a moving medium continuously moving on the image forming parts, first and second image forming devices, a test image density measuring device, and a control device. The first test image forming device forms a first test image on the medium by using the image forming parts in a first order. The second test image forming device forms a second test image on the medium. The control device controls image forming processing in the image forming parts based on a result of a density measurement of the second test image.

Abstract: A developing apparatus including a developer container which contains a first developer having a first charging polarity and a second developer having a second charging polarity opposite to the first charging polarity, a developer bearing member which bears the first and the second developers, a layer forming device which forms a first layer substantially composed of the first developer on the developer bearing member and forms a second layer composed of the first and the second developers on the first layer, a separating member which is provided downstream of the layer forming device and upstream of a developing position in a developer bearing and conveying direction of the developer bearing member to separate the second layer from the developer bearing member, whereby plural kinds of developers can be selectively supplied for a development.