There is provided an image forming system that includes an image forming apparatus including an image former that forms an image on a recording material, the image forming system including: recording material storage enabled to store the recording material; a recording material supplier that supplies the recording material from the recording material storage to the image former; a recording material information detection apparatus that is arranged outside the image forming apparatus and detects recording material information of the recording material; and a hardware processor that determines whether or not the recording material detected by the recording material information detection apparatus is settable into the recording material storage on the basis of the recording material information detected by the recording material information detection apparatus and information preset for the recording material storage.

A controller is configured to execute a larger gamut technology mode in which the controller performs image formation by controlling a ratio of a rotation speed of a development roller to a rotation speed of a photosensitive drum such that the ratio becomes a second speed ratio higher than a first speed ratio in a normal mode. The controller is configured to, when the controller executes the larger gamut technology mode, control transfer voltage based on a humidity around an image forming apparatus.

In an image-forming apparatus, a first sensor measures a first temperature and a relative humidity. A second sensor measures a second temperature. A controller is configured to perform: (a) calculating; (b) determining; and (c) executing. The (a) calculating calculates an internal temperature on the basis of the second temperature. The (a) calculating includes: when a target temperature of a heater is set to a printing temperature: (a-1) determining; and (a-2) correcting. The (a-2) correcting corrects, in response to determining in (a-1) that a temperature increase in the first temperature is greater than or equal to a first prescribed value and a humidity increase in an absolute humidity is greater than or equal to a second prescribed value, the internal temperature. The (c) executing executes, in response to determining in (b) that the internal temperature is greater than a threshold, a cool-down process to reduce a temperature inside a main casing.

An image forming apparatus includes a casing accommodating an image forming unit, a fan, a duct member, an electric component, and a sensor unit. The casing includes a cover member, an air inlet opening, and an air outlet opening. The fan is configured to take in air from an upstream side in the second direction and blow out the air to a downstream side in the second direction such that the air flow flowing through the air inlet opening, the fan, the duct member, and the air outlet opening is generated. The sensor unit is arranged within a region between the air inlet opening and a rotational axis of the fan in the first direction, and is arranged on an upstream side of the fan in the second direction.

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 drawer, an operation panel, and a sensor. The housing includes a first side wall having a first opening, and a second side wall having a vent and extending in a direction crossing the first side wall. The drawer supports a cartridge. The drawer is movable through the first opening between an inner position at which the drawer is accommodated in the housing and an outer position at which a part of the drawer is exposed to outside the housing. At least part of the operation panel protrudes from an outer surface of the second side wall. The sensor is arranged in the housing between the drawer and the second side wall. The sensor is configured to detect at least temperature or humidity of ambient air taken in through the vent.

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.

An image forming apparatus includes a photoconductive drum, a developing roller, a humidity sensor configured to detect a humidity, and a controller configured to execute a single-side printing, a first-double-side printing and a second double-side printing. The controller is configured to execute the first double-side printing in which images are printed at a first developing-bias voltage on both the first surface and the second surface of the sheet when the humidity detected by the humidity sensor is greater than a threshold value. The controller is configured to execute the second double-side printing in which an image is printed at a second developing-bias voltage, which is less than the first developing-bias voltage, on the second surface of the sheet when the humidity detected by the humidity sensor is equal to or less than the threshold value.

An adhesion apparatus includes: an image forming unit configured to form, through an electrophotographic process, an adhesive image of a powder adhesive on a sheet that is conveyed; and a control unit configured to control the image forming unit to use a first pattern in a first conveyance period, and use a second pattern different from the first pattern in a second conveyance period following the first conveyance period, as a formation pattern in an adhering section corresponding to part of a width direction orthogonal to a conveyance direction of the sheet.

According to one aspect of the present invention, an image forming apparatus includes a fixing unit comprising a fixing member configured to fix a toner image to a recording material, and a pressure member configured to form a first nip portion, a conveyance portion configured to form a second nip portion, and a control unit configured to execute, a conveyance mode of conveying the recording material so that the recording material is not looped between the first nip portion and the second nip portion prior to a predetermined timing during passing of the recording material of the first nip portion, and conveying the recording material so that the recording material is looped toward the pressure member from the predetermined timing until a trailing edge of the recording material has passed through the first nip portion.