A developing device has a developer container, a first stirring/transporting member, a second stirring/transporting member, a developer carrying member, a developer supply port, a developer discharge port, a regulating portion, and a height adjustment opening. The developer container has a partition partitioning between first and second transport chambers, and communication portions through which the first and second transport chambers mutually communicate. The first and second stirring/transporting members stir and transport developer in the first and second transport chambers in opposite directions respectively. The regulating portion regulates movement of the developer toward a developer discharge port. The height adjustment opening is formed in the partition, and when the height of the developer in the second transport chamber is equal to or higher than a predetermined height, part of the developer passes through the height adjustment opening and moves to the first transport chamber.

Provided is a developing device configured to develop an electrostatic latent image formed on an image bearing member by feeding a toner to the electrostatic latent image. The developing device includes a developing frame configured to form an inner space in which the toner and a carrier are to be mixed, a developing roller including an outer periphery to which the developer attaches where the developing roller feeds the toner included in the developer to the image bearing member. The developing device includes an agitator installed in the inner space and configured to mix and deliver the toner and the carrier in a direction parallel to an axial direction of the developing roller, and a plurality of concave portions arranged on a bottom surface of the developing frame.

A developing device includes a developer bearer to bear developer, a developer containing compartment to contain developer, and a developer conveyor including a shaft and disposed in the developer containing compartment. The developer bearer has magnetic poles adjacent to each other and identical in polarity, and the adjacent magnetic poles are disposed on a downward-rotation side where a surface of the developer bearer moves downward. The developer conveyor rotates to supply the developer to the surface of the developer bearer and collect the developer downstream, in a rotation direction of the developer bearer, from a developing range opposing a latent image bearer. The developing device further includes an inclined face disposed vertically below the adjacent magnetic poles, and the inclined face is inclined down toward the developer conveyor.

A developing device includes a developer bearer rotatable in a rotation direction and forming a developing range, a holder, and an entrance seal. The holder has a facing face facing the developer bearer upstream from the developing range in the rotation direction, a support face defining a part of an outer face of the developing device, and a relay face extending from one end of the support face to one end of the relay face connected to the facing face to form an acute tip portion closer to the developing range than the one end. The entrance seal has a free end projecting from the one end as a cantilever, and a length of the entrance seal from a tip of the free end of the entrance seal to the one end is shorter than a length of the relay face from the acute tip portion to the one end.

A powder container is provided. The powder container includes a powder storage and a conveyer. The powder storage stores a powder to be used for image formation and has a vent hole to pass air between an inside and an outside of the powder storage. The conveyer conveys the powder inside the powder storage. The vent hole is on an upper surface of the powder storage facing the conveyer.

A developing device of the present disclosure includes a developing roller, a toner supply roller, a regulation blade, a casing, a toner receiving support member, a toner receiving member, a vibration generation unit, and a vibration inhibition member. The toner receiving support member is disposed in the casing so as to be opposed to the developing roller or the toner supply roller in an area between the regulation blade and an image carrier. The toner receiving member has a toner receiving surface that receives toner dropping from the developing roller, and is supported so as to be swingable about an end edge thereof on a toner supply roller side as a fulcrum. In a state where the toner receiving member is not vibrating, the vibration inhibition member is in contact with each of both end portions of the toner receiving surface in a longitudinal direction thereof.

A developing device includes a developer bearer disposed facing a latent image hearer in a developing range to transport developer by rotation, a support to support the developer bearer and including a holder mount, a rod-shaped developer regulator disposed facing a surface of the developer bearer across a gap, and a holder secured to the holder mount of the support to hold the rod-shaped developer regulator. The rod-shaped developer regulator extends in an axial direction of the developer bearer.

A developing device is equipped with a developing roller rotationally driven for developing an electrostatic latent image formed on a surface of an image supporting body with toner, a screw rotationally driven of which a ratio of number of rotations to number of rotations of the developing roller being rotationally driven is constant, and a processor. The processor is configured to detect toner density in developer by using a sensor installed facing the screw, during rotationally drive of the screw, and detect information indicating a rotational position of the developing roller, based on ripples which occur in the toner density detected.

A developing device includes a developer bearer disposed facing a latent image bearer in a developing range to transport developer by rotation, a support to support the developer bearer and including a holder mount, a rod-shaped developer regulator disposed facing a surface of the developer bearer across a gap, and a holder secured to the holder mount of the support to hold the rod-shaped developer regulator. The rod-shaped developer regulator extends in an axial direction of the developer bearer.

A developing device includes a developer bearer, a magnetic field generator, a easing having an opening, a developer conveyor to rotate inside a developer containing compartment below the developer bearer, and a developer regulator. A side wall of the casing defines a bottom end of the opening, and the developer regulator is disposed on the side wall. The side wall includes an upper end face facing the developer bearer below an axis of the developer bearer and a curved inner face along an orbit of rotation of the developer conveyor, extending from below the developer conveyor toward the upper end face. On a virtual plane perpendicular to the axis of the developer bearer, an intersection between a tangent line to an upper end of the curved inner face and the surface of the developer bearer is in a range from a tangential magnetic-flux peak and a closest approach point.