A developing device has a developer container, first and second stirring members, and a developer carrying member. The developer container has a plurality of transport chambers including first and second transport chambers, a communication portion through which the first and second transport chambers mutually communicate in opposite end parts thereof in their longitudinal direction, a developer supply port, and a developer discharge port arranged in a downstream-side end part of the second transport chamber. The second stirring member has a second transport blade, a regulating portion formed on the downstream side of the second transport blade, a discharge blade formed on the downstream side of the regulating portion and discharging developer through the developer discharge port, and a disk formed at a position facing the downstream-side communication portion on the upstream side of the regulating portion and radially protruding over the entire circumference of a rotary shaft.

A waste toner collecting device includes an intermediate collection box, a conveying path, a conveying screw, an exhaust path and a floating toner collection chamber. The conveying path is provided in the intermediate collection box. The conveying screw is rotatable in the conveying path. Through the exhaust path, air containing a floating toner is sucked and passed. The floating toner collection chamber is provided on a part of the exhaust path in the intermediate collection box. The floating toner collection chamber has a discharge opening opened to an inside of the intermediate collection box and a discharge door. Rotation of the conveying screw in a normal direction turns the discharge door into a storage position where the discharge opening is closed. Rotation of the conveying screw in a reverse direction turns the discharge door into a discharge position where the discharge opening is opened.

A developing device includes a developer container that accommodates an electrostatic image developer including toner containing a toner particle and a zinc stearate particle, a ratio (D.sub.T/D.sub.S) of a volume-average particle size (D.sub.T) of the toner particle to a volume-average particle size (D.sub.S) of the zinc stearate particle being about 1.9 or more; a developer carrier that supplies the toner to an image carrier; a supply conveyor that supplies the electrostatic image developer while conveying the electrostatic image developer; a mixing conveyor that conveys the electrostatic image developer while mixing the electrostatic image developer; and a partition disposed between the supply conveyor and the mixing conveyor. The electrostatic image developer is moved from the supply conveyor to the mixing conveyor through a first passage and is moved from the mixing conveyor to the supply conveyor through a second passage.

A toner conveying device includes a case that can store therein toner to be conveyed, a conveyance member rotatably supported at both ends thereof by the case and configured to rotate to convey the toner inside the case in a conveying direction set in advance, and a pushing member pushed against the conveyance member and configured to slide on an outer peripheral portion of the conveyance member as the conveyance member rotates. The pushing member includes a first sheet member having flexibility and abutting on the outer peripheral portion in a first direction intersecting with a rotational axis direction of the conveyance member to push the conveyance member and a second sheet member having flexibility and abutting on the outer peripheral portion in a second direction, which is different from the first direction, intersecting with the rotational axis direction to push the conveyance member.

An example printing fluid apparatus, for a printing system, comprises a printing fluid reservoir to store printing fluid for use in a print job and a printing fluid channel to route printing fluid from the reservoir to the reservoir and to route printing fluid from a printing station of the printing system to the reservoir. The fluid channel comprises a port to introduce printing fluid from a printing fluid cartridge into the fluid channel such that the introduced printing fluid from the printing fluid cartridge at least partially mixes with printing fluid in the fluid channel.

A developing device includes a developer container, a developer carrier, and first and second members for stirring/conveying. The developing container has a first partition wall between first and second chambers, communication portions through which those chambers communicate at opposite ends of the first partition wall, a developer supply port, and a developer discharge portion. The first member stirs and conveys developer in the first chamber in a first direction. The second member stirs and conveys developer in the second chamber in a second direction and includes a regulating portion and a discharging blade. The developer container includes a second partition wall between the first chamber and the regulating portion. The second partition wall is lower than the first partition wall, and an upper end part of the second partition wall is between upper and lower end parts of the rotary shaft of the second stirring/conveying member.

A developing device includes a holding body that holds a developer; an agitating unit that agitates the developer; a supply unit that supplies the developer that flows in from the agitating unit to the holding body; a filling portion provided above the agitating unit and filled with the developer; a closing portion that closes a lower portion of the filling portion, and causes the developer to drop from the filling portion into the agitating unit in a case where the closing portion is removed; and a duct portion that connects a space in the filling portion and a portion above the holding body.

A device to develop an electrostatic latent image in an imaging apparatus includes first and second passages coupled to each other through first and second openings to form a circulation passage. A first stir-and-transport member is located in the first passage and includes a first helical blade to stir and transport a developer from the first opening to the second opening along the first passage in a first direction and to supply the developer to a developing roller. A second stir-and-transport member is located in the second passage and includes a second helical blade to stir and transport the developer from the second opening to the first opening along the second passage in a second direction. A developer discharge pipe is coupled to the developer container to communicate with a downstream side of the first passage. The first stir-and-transport member includes a first reverse helical blade located downstream of the first helical blade and disposed downstream of the second opening. The pitch of the first reverse helical blade is between approximately 0.5 times and 1.5 times the pitch of the first helical blade.

An image forming apparatus (1) includes a casing (21) having a toner conveyance path (34); a screw (24) conveying a toner in the toner conveyance path (34) in a predetermined conveyance direction; and a downstream side bearing (25) rotatably supporting a downstream side end portion of the screw (24) in the conveyance direction, wherein the screw (24) includes: a shaft (51) extending in the conveyance direction; and a spiral fin (52) provided around an outer circumferential face of the shaft (51), the shaft (51) has a downstream side insertion part (54) inserted into the downstream side bearing (25), and the downstream side insertion part (54) has an outer diameter larger than an outer diameter of a downstream side end portion of the fin (52) in the conveyance direction.

A developing device includes a developer container, a developer carrier, and first and second members for stirring/conveying. The developing container has a first partition wall between first and second chambers, communication portions through which those chambers communicate at opposite ends of the first partition wall, a developer supply port, and a developer discharge portion. The first member stirs and conveys developer in the first chamber in a first direction. The second member stirs and conveys developer in the second chamber in a second direction and includes a regulating portion and a discharging blade. The developer container includes a second partition wall between the first chamber and the regulating portion. The second partition wall is lower than the first partition wall, and an upper end part of the second partition wall is between upper and lower end parts of the rotary shaft of the second stirring/conveying member.