An image forming apparatus includes an image forming device that forms an image on a sheet and executes predetermined image forming processing, a reception device that receives a user instruction, a sensor that acquires ambient temperature information, and at least one controller that prohibits execution of the predetermined image forming processing for a predetermined period if any of a plurality of conditions including a first condition and a second condition is satisfied, wherein the first condition is a condition that a plurality of pieces of temperature information acquired at a plurality of timings have a predetermined relationship and the second condition is a condition that a predetermined instruction is received.

An image forming apparatus includes an image forming unit, a storage portion to which a heating unit configured to heat the sheet stored in the storage portion is detachably attached, a conveyance unit, a detection unit configured to detect attachment of the heating unit to the storage portion, and a control unit configured to control the conveyance unit such that a standby time by which conveyance of the sheet fed from the storage portion is stopped is shorter when the detection unit detects the heating unit than when the detection unit does not detect the heating unit.

An image forming apparatus includes a control portion that performs a double-side image forming mode after performing a single-side image forming mode on a predetermined number of sheets in a state in which a heating unit is not attached to a sheet storage portion. The control portion sets an arrival timing of a first sheet to a transfer portion in the double-side image forming mode to be later than an arrival timing of a first sheet to the transfer portion in the double-side image forming mode in a case the control portion performs the double-side image forming mode after performing the single-side image forming mode on the predetermined number of sheets in a state in which the heating unit is attached to the sheet storage portion.

A high-voltage electrical circuit board is located in a first region that is a region at one side of photosensitive drums in a first direction and outside of the photosensitive drums in the first direction. A first motor drives a conveyance mechanism. A second motor is located in a second region and drives each photosensitive drum. A third motor is located in the second region and drives each developing roller to rotate and to drive a separation mechanism configured to individually move the developing rollers between a contact position and a separation position. A control board is located in the second region. The control board includes a controller configured to control a first applying circuit, the first motor, the second motor, and the third motor. The first motor, the second motor, the third motor, and the control board are located at different positions from one another in the second region.

A server includes a transceiver and a controller. The transceiver is configured to facilitate communication with a plurality of image forming apparatuses. The controller is configured to receive adjustment information from each of the plurality of images forming apparatuses, determine an updated adjustment value to be used in each of the plurality of image forming apparatuses based on the adjustment information received from of each of the plurality of image forming apparatuses, and transmit adjustment update information including the updated adjustment value to each of the plurality of image forming apparatuses.

A powder amount detector detects an amount of powder in a powder container of a cylindrical shape arranged horizontally. The powder amount detector includes a pair of measuring electrodes configured to detect capacitance between the pair of measuring electrodes to detect the amount of powder. The pair of measuring electrodes is disposed around the powder container. One of the pair of measuring electrodes has a flat shape, and the other of the pair of measuring electrodes has an arc shape following a shape of the powder container.

An image forming apparatus including a revolving member, a first-transfer member, a second-transfer member that transfers the toner image on the revolving member onto a recording medium, a removing member downstream of the second-transfer member to remove a deposit on the revolving member, a fixing device that generates heat and that fixes the toner image transferred on the recording medium, a generating member that causes air to flow from the fixing device toward the revolving member, and an executing unit that executes a removal mode including causing the fixing device to generate heat, causing the generating member to operate, causing the revolving member to operate, causing the first-transfer member to operate so as to transfer a cleaning image as a toner image onto the revolving member, and causing the removing member to remove the cleaning image from the revolving member without transferring the cleaning image onto the recording medium.

A humidity detection device includes a humidity sensor, a resistor connected to one-side of the humidity sensor, a first switching part connected to the resistor; a diode connected to the first switching part; a second switching part connected to the other-side of the humidity sensor, a potential difference generating part connected to the second switching part, a power supply supplying a voltage, and a control part applying the voltage as an alternating voltage to the humidity sensor by controlling the first switching part and the second switching part. The control part applies a current to the diode, the resistor and the humidity sensor in a first direction by connecting the second switching part to the ground, and applies the current to the resistor and the humidity sensor in a second direction, which is an opposite direction from the first direction, by connecting the first switching part to the ground.

An image forming apparatus includes a housing, a conveying member not used in simplex printing, a duct, a blower, and control circuitry. The duct includes an intake and an opening. The intake is disposed at a first end of the duct. The intake sucks air from outside of the image forming apparatus. The opening is disposed at a second end of the duct different from the first end of the duct. The duct is disposed opposite the conveying member. The blower is disposed in the duct. The blower blows air sucked from the intake to the conveying member through the opening. The control circuitry controls the blower to blow air to the conveying member at least in the simplex printing.

An image forming apparatus includes an image forming portion, a fixing portion, a duct and a water vapor moving portion through which water vapor generated in the fixing portion moves. The water vapor moving portion is cooled by air blowing in the duct.