An image forming apparatus includes an image bearing member, an intermediate transfer belt, and a contact member. The intermediate transfer belt includes a base layer, a surface layer formed on an outside of the base layer, and an inner surface layer formed on an inner side of the base layer. A position at which the contact member and the intermediate transfer belt contact is arranged on a downstream side of the intermediate transfer belt in a rotation direction of the intermediate transfer belt. Rv>Rs1 and Rs2>Rs1, and Rs2/Rv≤40 are satisfied where Rv(Ω) is a volume resistance value of the intermediate transfer belt in a thickness direction, Rs1(Ω) is a first surface resistance value of the inner surface layer side in a surface direction, and Rs2(Ω) is a second surface resistance value on the surface layer side in a surface direction.

An image forming apparatus includes an image bearing member that bears a toner image, a transfer unit having an endless belt, a positioning unit that positions the transfer unit, and a secondary transfer member. The secondary transfer member is in touch with the endless belt to form a secondary transfer portion. When the toner image is transferred to the endless belt from the image bearing member, the secondary transfer member transfers the toner image from the endless belt at the secondary transfer portion to a transfer material. The positioning unit includes a first abutting face to position the transfer unit in a conveyance direction and a second abutting face to position the transfer unit in a direction opposite to the conveyance direction. An attaching/detaching direction of the transfer unit is a direction intersecting with a surface of the transfer material to which the toner image is transferred.

In an image forming apparatus including a transfer member that primarily transfers a developer image from an image bearing member onto an intermediate transfer belt by applying an electric current to an intermediate transfer belt in a circumferential direction, a control unit which executes a first mode in which to rotate the intermediate transfer belt and a second mode in which to rotate the intermediate transfer belt at a rotation speed higher than that in the first mode. The control unit performs control such that an absolute value of a second voltage to be applied to the transfer member in a case of performing primary transfer in the second mode is less than an absolute value of a first voltage to be applied to the transfer member in a case of performing the primary transfer in the first mode.

An image forming apparatus includes an image forming portion, a rotatable endless belt, a plurality of stretching rollers including an inner roller and an upstream roller, an outer member, a guiding member, a sheet-like pressing member, and a coating member. The coating member is disposed on the pressing member so as not to contact the belt and is electrically grounded or electrically conducted to the guiding member. The coating member is formed of a material lower in surface resistivity than the pressing member.

A drive transmitting device includes a first gear; a second gear in engagement with the first gear; wherein a first tooth which is at least one of teeth of the first gear has a tooth surface contacting a tooth of the second gear, wherein the tooth surface has such a shape that a contact point of the first tooth of the first gear to the tooth of the second gear is in a region of a first gear side with respect to a line of action which is formed by movement of a contact point between a tooth of the second gear and a second tooth of the first gear immediately before the first tooth with respect to a rotational moving direction of the first gear.

A mounting member to be mounted on a member that moves in a traveling direction includes: a rectangular sheet member; and an attachment portion having a first surface bonded to one end portion of a reverse surface of a downstream side portion of the sheet member in the traveling direction, the attachment portion being detachably attached to an attachment-receiving portion and having a surface facing a direction different from a direction of the first surface and bonded to the sheet member.

An image forming apparatus includes: an annular transfer belt to which an image is transferred; a transfer roller that transfers an image to a recording medium when the recording medium passes through a transfer area formed between the transfer roller and the transfer belt; a drive mechanism that causes the transfer roller to rotate; and a speed adjustment mechanism that adjusts a rotational speed of the transfer roller achieved by the drive mechanism in units of a cycle of the transfer roller, and switches between a first adjustment pattern and a second adjustment pattern to execute switched adjustment pattern in a cycle including a state in which the transfer roller transports the recording medium, the first adjustment pattern for adjusting the rotational speed of the transfer roller, the second adjustment pattern for adjusting the rotational speed of the transfer roller with a pattern different from the first adjustment pattern.

An image forming apparatus includes a formation target that is wound around rotating bodies including a driving roller and transported by the rotating bodies including the driving roller while forming a shape having linear portions each of which forms a different angle, which is an acute angle or an angle of zero degrees, with a horizontal direction when viewed in an axial direction of the driving roller, first image forming bodies that are arranged along one of the linear portions in such a manner as to be spaced apart from each other by a first distance and that form images onto the formation target, and second image forming bodies that are arranged along another one of the linear portions, the other linear portion forming the angle larger than the angle formed by the one linear portion, in such a manner as to be spaced apart from each other by a second distance shorter than the first distance and that form images onto the formation target.

An image forming apparatus includes an image forming target to be transported along one direction, three or more image formers arranged away from each other along the one direction and configured to form images on the image forming target, and an image forming target winding motion correcting roller rotatably in contact with an inner peripheral surface of the image forming target and positioned on a downstream side of the image former at an upstream end in a transport direction of the image forming target so that plural image formers are positioned on a downstream side of the image forming target winding motion correcting roller. A distance between the plural image formers positioned on the downstream side of the image forming target winding motion correcting roller is an integral multiple of an outer peripheral length of the image forming target winding motion correcting roller.

An image forming apparatus includes: a fixing cylinder that is rotatably supported, that has a groove formed in an outer portion thereof in a rotational radial direction thereof, and that causes an image transferred to a recording medium to be fixed to the recording medium when the recording medium passes along an outer surface of the fixing cylinder in the rotational radial direction; a delivery cylinder that is rotatably supported; a circulating member that is loop-shaped and wrapped at least around the fixing cylinder and the delivery cylinder; plural holding members configured to hold the recording medium when the recording medium passes around the delivery cylinder toward the fixing cylinder, the holding members being supported by the circulating member such that the holding members are arranged in a length direction of the circulating member with predetermined intervals therebetween, each holding member being disposed in the groove when the holding member passes along the outer portion of the fixing cylinder; and a pressure unit that is rotatably supported and that causes the recording medium to pass between the pressure unit and the fixing cylinder while a pressure is applied between the pressure unit and the fixing cylinder, the pressure unit coming into contact with an end portion of the groove in a rotation direction of the fixing cylinder before or after a period from when one of the holding members starts a holding operation for holding the recording medium to when the holding operation is completed.