An image forming apparatus includes a carrying part that carries media, a supply part that forwards the media to the carrying part piece by piece, wherein when a preceding medium is detected to have been fed to the carrying part, a succeeding medium is next fed to the carrying part, and a carrying controller that stops the preceding medium at a stop position of the media before the preceding medium is carried to the image forming process. The carrying controller obtains a medium length of the preceding medium in the carrying path, and changes the stop position of the preceding medium based on the medium length such that the trailing edge of the preceding medium is maintained distant from the leading edge of the succeeding medium while the preceding medium stops at the stop position.

The image forming apparatus includes a control unit for converting image information into an image signal and output the image signal with reference to a timing signal, a sheet feeding control unit for feeding a recording material, an image forming unit for forming the image on a photosensitive drum based on the image signal output from the control unit, a transmission unit for transmitting a length of the image corresponding to a length of an output period of the image signal, an automatic sheet length detection mechanism for acquiring a length of the recording material in a conveyance direction thereof, and an image control unit for controlling a time interval at which the timing signal is output based on the size of the image and the size of the recording material.

A motor control device includes a first control unit and a second control unit. The first control unit includes an issuing unit that issues a command that schedules a next operation of a motor according to an instruction from a controller. The second control unit includes a receiving unit that receives the command, a detecting unit that detects a state of the motor, a determining unit that makes a determination as to whether to drive the motor to perform the operation according to the state detected by the detecting unit, and an executing unit that drives the motor to perform the operation scheduled by the command as determined by the determination.

An image forming apparatus includes an image bearing member, an image forming portion, an endless belt, a plurality of stretching rollers including an inner roller, an outer roller, a position changing mechanism capable of changing a position of the inner roller to a first position and a second position positioned downstream of the first position with respect to a rotational direction of the endless belt, a feeding member, a feeding member driving portion, and a controller. A feeding start timing of a recording material by the feeding member depends on the position of the inner roller during transfer of a toner image onto the recording material.

An image forming apparatus includes an image bearing member, a transfer rotating body, a feeding means and a control means that controls a feeding speed of a recording material in a feeding portion at the feeding means. Wherein a first timing is a timing during when a rear end of the recording material with respect to a feeding direction passes through a transferring portion and a second timing is a timing when the rear end of the recording material is separated from the image bearing member after passing through the transferring portion, the control means can control the feeding means for one recording material so that a feeding speed of the recording material at the second timing in the feeding portion becomes faster than that of at the first timing in the feeding portion.

After outputting a first start signal for causing an image forming unit to start formation of an image for a first side of an i-th sheet, a controller causes a feeding member to start feeding of the i-th sheet, and determines whether or not the i-th sheet has already been detected by a detector. In a case where the i-th sheet has been detected before a predetermined time has elapsed, the controller outputs a second start signal for causing the image forming unit to start formation of an image for second side of an (i−1)th sheet. In a case where the i-th sheet has not been detected before the predetermined time has elapsed, the controller outputs the second start signal after the i-th sheet is detected.

According to one embodiment, an image forming apparatus includes: a registration roller; a motor configured to drive the roller; and a controller configured to control the motor. The roller is disposed at a first position on a conveyance path of paper on which an image is to be formed, and sends out the paper toward a second position on the conveyance path. The second position is downstream from the first position on the conveyance path and is an image transfer position on the paper. The controller controls the motor by using both speed control and position control when the leading end of the paper is at a position from the first position to the second position, and controls the motor by using only the speed control when the leading end of the paper reaches the second position.

An image forming apparatus includes an image forming unit, a fixing unit, and a control unit. The image forming unit forms a toner image on a recording material. The fixing unit heats and fix the toner image formed on the recording material to the recording material in a fixing nip portion. The fixing unit includes a heater and a nip portion forming member that forms the fixing nip portion to pinch and convey the recording material. The control unit control the power to be supplied to the heater so as to change a temperature gradient at time of warm-up of the fixing unit to a target temperature in accordance with time from start of power supply to the heater until entry of the recording material into the fixing nip portion.

A medium conveyance device includes: a plurality of roller pairs arranged in a width direction of a recording medium, the plurality of roller pairs including at least two end-side roller pairs respectively located near two ends of the recording medium in the width direction and at least one center-side roller pair located near a center of the recording medium in the width direction, the plurality of roller pairs each including a pair of rollers that convey the recording medium while nipping the recording medium and are individually contactable with and separable from each other; and a contact and separation mechanism that moves a first roller of the pair of rollers of the at least one center-side roller pair in a thickness direction of the recording medium or moves a first roller of the pair of rollers of each of the at least two end-side roller pairs in the thickness direction of the recording medium, to make a difference in separation timing.

An image forming apparatus includes a conveying unit, an image forming unit, a fixing unit, a first driving unit, a second driving unit, a transmission unit to transmit an ultrasonic wave, and a reception unit. Where a determination is made that a timing at which excitation of the first driving unit is switched or a timing at which excitation of the second driving unit is switched overlaps with a timing to obtain a value of the ultrasonic wave received by the reception unit, the transmission unit does not transmit an ultrasonic wave. Where a determination is made that the timing at which the excitation of the first driving unit is switched or the timing at which the excitation of the second driving unit is switched does not overlap with the timing to obtain the value of the received ultrasonic wave, the transmission unit transmits an ultrasonic wave.