A toner supply device includes a supply pipe, a first conveying pipe, a second conveying pipe, a first conveying member, a second conveying member, and a loosening member. The loosening member is arranged in the supply pipe reciprocatably in the extending direction of the supply pipe. The first and second conveying pipes are arranged side by side in a direction intersecting their extending directions so as to join together at a confluence portion to which the supply pipe is connected. The loosening member is coupled with each of the first and second conveying members at the confluence portion and extends inward of the supply pipe.

A waste toner storage container includes a container body, a toner storage chamber, and a paddle. The toner storage chamber includes an introduction port, a first space, and a second space. The introduction port receives waste toner. The first space stores the introduced waste toner, and extends in a first direction. The second space is disposed in an end portion of the first space in a second direction orthogonal to the first direction. The paddle includes a shaft, a first plate, and a secondplate. The shaft is disposed in the first space, extends along the first direction, and is elongated. The first plate is formed on an outer peripheral surface around a central axis of the shaft, and conveys the waste toner in the first direction. The second plate is formed on the outer peripheral surface of the shaft, and conveys the waste toner toward the second space.

An image forming apparatus includes an image carrier, a toner supply unit, an application roller adjacent to the image carrier, a toner measuring unit, and a control unit. The toner supply unit supplies toner to the image carrier. The application roller applies a lubricant to the image carrier. The toner measuring unit measures an amount of toner transferred from the image carrier to the application roller. The control unit adjusts the supply of toner to be supplied to the image carrier in accordance with the amount of toner measured by the toner measuring unit.

A toner conveying apparatus includes a frame body, a conveyance member, a light transmission portion, a light emission portion, a light reception portion, and a rubbing member. The frame body forms a conveyance passage surrounded by a wall portion and is provided with a reception inlet for receiving toner from outside. The conveyance member is provided in the conveyance passage and rotates around a first rotation axis to convey the toner. The light transmission portion that is provided in the wall portion and has translucency. The light emission portion emits light toward an inside of the conveyance passage through the light transmission portion. The light reception portion receives the light emitted from the light emission portion through the light transmission portion. The rubbing member rubs on the light transmission portion by being rotated around a second rotation axis extending in a direction crossing the first rotation axis.

An image forming apparatus includes a developer container to accommodate developer containing toner, a developer bearing member to rotate while bearing the developer accommodated in the developer container and develop the electrostatic latent image borne on an image bearing member into a developer image, a detection portion to output remainder amount information corresponding to an amount of the developer accommodated in the developer container, and a notification portion capable of notifying a first state indicating that a remainder amount of the developer accommodated in the developer container is a first amount or more and a second state indicating that the remainder amount of the developer accommodated in the developer container is less than the first amount. The notification portion notifies one of a plurality of states including the first state and the second state on a basis of the remainder amount information output from the detection portion.

An image forming apparatus includes an image bearing member, a replenishment unit, an agitation member, a drive source, a control unit, a memory unit, and a remaining amount detection unit. The control unit performs (1) a first operation to drive the drive source for a first time in a case where it is judged based on the output value of the remaining amount detection unit that the toner has increased, and (2) a second operation to drive the drive source for a second time that is shorter than the first time in a case where it is judged based on the output value of the remaining amount detection unit that the toner has not increased.

A waste toner storage container includes a container body, a toner storage chamber, and a paddle. The toner storage chamber includes an introduction port, a first space, and a second space. The introduction port receives waste toner. The first space stores the introduced waste toner, and extends in a first direction. The second space is disposed in an end portion of the first space in a second direction orthogonal to the first direction. The paddle includes a shaft, a first plate, and a second plate. The shaft is disposed in the first space, extends along the first direction, and is elongated. The first plate is formed on an outer peripheral surface around a central axis of the shaft, and conveys the waste toner in the first direction. The second plate is formed on the outer peripheral surface of the shaft, and conveys the waste toner toward the second space.

An image forming apparatus, including: a photoconductor; a developing device; a developer storage; a supplier configured to supply developer; an optical sensor; and a controller configured to execute: a developing process of developing an electrostatic latent image on the photoconductor; a usage-amount obtaining process of obtaining a usage amount of the developer; a supplying process of supplying the developer to the developing device every time when the obtained usage amount becomes equal to or greater than a first threshold; and a detecting process of detecting, by the optical sensor, an amount of the developer in the developing device every time when the obtained usage amount becomes equal to or greater than a second threshold larger than the first threshold, and wherein the controller is configured to execute the detecting process in a period different from a period in which the developing process is being executed.

An image forming apparatus includes an image forming device and circuitry. The image forming device forms an image with colorants of different colors. The circuitry determines whether there is a possibility that a shortage of a colorant adhesion amount occurs in primary-color image formation using a colorant of a primary color and cause the image forming device to perform two-color image formation in which only secondary-color image formation using a colorant of a secondary color different from the colorant of the primary color is added to the primary-color image formation using the colorant of the primary color to form an image to be formed with the colorant of the primary color, when the circuitry determines that there is a possibility that the shortage of the colorant adhesion amount occurs in the primary-color image formation using the colorant of the primary color.

An image forming apparatus includes an image bearing member, a replenishment unit, an agitation member a drive source, a control unit, a memory unit, and a remaining amount detection unit. The control unit performs (1) a first operation to drive the drive source for a first time in a case where it is judged based on the output value of the remaining amount detection unit that the toner has increased, and (2) a second operation to drive the drive source for a second time that is shorter than the first time in a case where it is judged based on the output value of the remaining amount detection unit that the toner has not increased.