An image forming apparatus includes a transfer unit for transferring a toner image onto a sheet, a fixing device for fixing the image, the fixing device including a belt, a pressure element for pressing against the belt, a heating member on the belt including a heat generating element and electrodes on both sides of the heat element in a sheet conveyance direction and connected to the heat element, and an adjustment mechanism for moving one of the heating member and the pressure element in a manner to move the one closer to or away from the other, and a controller for controlling the adjustment mechanism so that a distance between the heating member and the pressure element becomes a first distance during a fixing process and a second distance larger than the first distance during temperature raising of the heating member, which is conducted before the fixing process.

An image forming apparatus includes a fixing device and a drive transmission mechanism. The fixing device fixes an image on a sheet by application of heat and pressure. The drive transmission mechanism changes a conveying speed of the sheet in the fixing device between an image forming mode and a lamination mode. The conveying speed of the sheet in the fixing device in the lamination mode is lower than the conveying speed of the sheet in the fixing device in the image forming mode.

An image forming apparatus includes a control unit that controls a conveyance velocity of conveying a recording medium by a fixing unit, to form a loop in the recording medium between a transfer nip portion and a fixing nip portion, in which the control unit controls the conveyance velocity to decrease the loop when a rear end of the recording medium reaches a first position that is apart upstream, in the conveyance direction, from a conveying nip portion of a conveying unit, by a distance that corresponds to a circumference length of a pressure-applying rotating member multiplied by an integer.

An image forming apparatus includes a transfer unit for transferring a toner image onto a sheet, a fixing device for fixing the image, the fixing device including a heating member including a heat generating element and electrodes on both sides of the heat generating element in a sheet conveyance direction and connected to the heat generating element, and a pressure element for pressing against the heating member, and a controller for controlling an adjustment mechanism so that a distance between the heating member and the pressure element becomes a first distance during a fixing process and a second distance larger than the first distance during temperature raising of the heating member, which is conducted before the fixing process.

An image forming apparatus includes: a first rotatable member; a second rotatable member that presses against the first rotatable member in a pressed state and separates from the first rotatable member in a separated state; and a hardware processor that sets a target speed of the second rotatable member based on a change in speed of the second rotatable member between a first speed in the separated state and a second speed in the pressed state.

A fixing device includes a heated rotational body, a heating unit, a pressing rotational body, a drive unit, a light emitting unit, a light receiving unit, and a drive control part. The heated rotational body has a reflection member. The drive unit rotates the pressing rotational body. The light emitting unit emits infrared light. The light receiving unit receives the infrared light reflected on the reflection member, and receives radiation light of the heated rotational body. The light receiving unit detects a temperature of the heated rotational body based on a receiving of the radiation light. The drive control part obtains a rotational speed of the heated rotational body based on a light receiving period of the infrared light in the light receiving unit and a circumference determined depending on the temperature of the heated rotational body, and controls the drive unit based on the obtained rotational speed.

An image forming apparatus includes a control unit configured to perform a first mode, a second mode, and a third mode. The first mode is a mode in which a sheet conveyance unit is controlled so that an arrival time from a passage of a trailing edge of a preceding sheet through a nip portion to an arrival of a leading edge of a succeeding sheet succeeding to the preceding sheet at the nip portion becomes a first time. The second mode is a mode in which the sheet conveyance unit is controlled so that the arrival time becomes a second time. The third mode is a mode in which the sheet conveyance unit is controlled so that the arrival time becomes a third time. The second time is longer than the first time, and the third time is longer than the second time.

An image forming apparatus includes a control unit that controls a conveyance velocity of conveying a recording medium by a fixing unit, to form a loop in the recording medium between a transfer nip portion and a fixing nip portion, in which the control unit controls the conveyance velocity to decrease the loop when a rear end of the recording medium reaches a first position that is apart upstream, in the conveyance direction, from a conveying nip portion of a conveying unit, by a distance that corresponds to a circumference length of a pressure-applying rotating member multiplied by an integer.

A fixing device includes a rotatable fixing belt, a pad, a rotatable pressing member, a pressing member driving source, an auxiliary driving roller, and a transmission mechanism for transmitting a driving force from the pressing member driving source to the auxiliary driving roller, wherein a peripheral speed of the auxiliary driving roller is faster than a peripheral speed of the pressing member, and a steering roller provided so as to stretch the fixing belt at the inner surface of the fixing belt in a position downstream of the auxiliary driving roller and upstream the pad with respect to a rotational direction of the fixing belt. The steering roller adjusts a position of the fixing belt with respect to a widthwise direction of the fixing belt by inclining the fixing belt so as to be positioned within a predetermined range.

A fixing apparatus includes a heating rotary member and a pressing rotary member, which form a nip portion, at which a toner image is fixed to a recording material, a mixture job is a job with a mixture of recording materials including a recording material with a first grammage and a recording material with a second grammage greater than the first grammage, one of a plurality of modes is performable in the mixture job, in which a maximum value of an amount of toner on the recording material with the first grammage is greater than a maximum value of the amount of toner on the recording material with the second grammage in the first mode whereas the maximum value on the recording material with the first grammage is equal to the maximum value on the recording material with the second grammage in the second mode.