A developing device includes a developing container, first and second stirring-conveyance members, a developer carrier, a toner concentration sensor, a scraper, and a scraper attachment unit. The second stirring-conveyance member includes a rotation shaft, a first spiral blade to convey developer in an axial direction, and a second spiral blade to overlap a region where the first spiral blade is formed, which is opposite to the first spiral blade in phase, and lower than the first spiral blade in height in a radial direction. An absent region, where the second spiral blade does not exist, is formed in one pitch of the first spiral blade, the one pitch facing the toner concentration sensor. The scraper attachment unit is formed to extend, along a straight line passing through intersection points of the first and second spiral blades and parallel to the rotation shaft, into the absent region.

A stirring/conveying member has a rotary shaft rotatably supported in a powder container, a first helical blade formed on the circumferential surface of the rotary shaft and conveying powder in the axial direction by the rotation of the rotary shaft, and a second helical blade formed on the circumferential surface of the rotary shaft to overlap the forming region of the first helical blade, spiraling in the opposite phase to the first helical blade, and having a smaller radial height than the first helical blade. The first helical blade crosses the second helical blade at least at one place in one turn about the rotary shaft. At least one of the radial heights of the first and second helical blades equals zero at the intersection of the first and second helical blades.

According to an image forming device of the present disclosure, a required replenishment amount is calculated based on a printing rate derived from image data, and toner is replenished to a development device by a toner replenishment device for a required replenishment time in accordance with the required replenishment amount. Then, a time difference obtained by subtracting a printing time per sheet from the required replenishment time is accumulated, and a determination regarding forcible replenishment of the toner is made based on a comparison between an accumulated required replenishment time and an accumulated required replenishment time threshold value.

A toner container includes containing chambers, a shaft member, rotary members, and stirring members. The containing chambers are arrayed in a first direction and partitioned from each other. The containing chambers contain respective toners of different colors. The shaft member extends in the first direction, passes through the containing chambers, and is rotatable about a rotational axis extending in the first direction. The rotary members are disposed in the respective containing chambers and each have a through-hole extending in the first direction. The rotary members are rotatable in response to rotation of the shaft member in an inserted state of the shaft member in the through-holes. The stirring members are supported by the respective rotary members and each extend in a second direction intersecting the first direction. The stirring members are pivotable in response to rotation of the respective rotary members. The stirring members have different pivoting positions upon pivoting.

According to one embodiment, a developing device includes a casing for accommodating a developer, the casing extending in a first direction and including a first insertion portion and a first through-hole that extends from the first insertion portion in a second direction, a first sealing member inside the first insertion portion, and a first rotating body extending in the first direction through the first insertion portion and configured to transport and agitate the developer in the casing. The first sealing member is in contact with an outer surface of the first rotating body and configured to slide along the outer surface of the first rotating body.

A toner cartridge includes a housing configured to contain toner. The housing includes a main body, a first side plate, and a second side plate. The main body has a tubular shape extending in a first direction. The main body is made of paper. The first side plate is located at one end of the main body in the first direction. The first side plate is made of resin. The second side plate located at an other end of the main body in the first direction. The second side plate is made of resin. The main body includes a peripheral surface having a discharge opening. The discharge opening is configured to discharge toner in the housing.

A toner container includes containing chambers, a shaft member, rotary members, and stirring members. The containing chambers are arrayed in a first direction and partitioned from each other. The containing chambers contain respective toners of different colors. The shaft member extends in the first direction, passes through the containing chambers, and is rotatable about a rotational axis extending in the first direction. The rotary members are disposed in the respective containing chambers and each have a through-hole extending in the first direction. The rotary members are rotatable in response to rotation of the shaft member in an inserted state of the shaft member in the through-holes. The stirring members are supported by the respective rotary members and each extend in a second direction intersecting the first direction. The stirring members are pivotable in response to rotation of the respective rotary members. The stirring members have different pivoting positions upon pivoting.

A toner agitator assembly according to one example embodiment includes a shaft rotatable about a rotational axis. A wiper extends outward from the shaft and is rotatable with the shaft. The wiper is composed of a flexible film material. The wiper includes at least two fingers formed in a distal end of the wiper relative to the shaft. The fingers are individually deflectable counter to an operative rotational direction of the shaft.

An image forming apparatus includes an image forming portion configured to form an image on a recording media and including a developer bearing member configured to bear developer and carry the developer, a regulating portion disposed opposite to the developer bearing member and configured to regulate an amount of the developer on the developer bearing member, a first chamber configured to supply the developer to the developer bearing member, and a second chamber configured to communicate with the first chamber to form a circulating route of the developer. In addition, a first feeding member feeds the developer in the first chamber, and a second feeding member feeds the developer in the second chamber. A control portion executes, in a non-image forming state, a mode of driving the developer bearing member in a condition in which the first feeding member is stopped.

A developing device includes a developer carrying member for developing an electrostatic image with a developer, a developer container including a developing opening, and a developer supplying member for supplying the developer to a developing chamber through the developing opening. The developer supplying member includes a shaft member rotatably supported by the developer accommodating portion and a feeding member, wherein the feeding member includes a first feeding portion and a second feeding portion. The first feeding portion is provided in a downstream side, and the second feeding portion is provided in an upstream side with respect to a rotational direction of the shaft member.