A developing device detachably mountable to an image forming apparatus includes a developer carrying member and a developer accommodating container including first and second chambers for circulating developer and a supply opening. An openable mechanism maintains a closed state of a discharge opening in the developer accommodating container before initial drive input into the developing device and opens and closes the discharge opening in interrelation with a mounting and demounting operation of the developing device after initial drive of the developing device. The openable mechanism includes a shutter, a spring member for urging the shutter in a closing direction, a sealing sheet for unsealably sealing the discharge opening and for sealing an initial developer in the accommodating container, and a winding-up shaft for winding up the sealing sheet. The sealing sheet is removed from the discharge opening after the initial drive of the developing device.

An image forming apparatus includes a toner image forming section, a selection section, and a performing unit. The toner image forming section forms a toner image. The selection section allows a user to select a condition regarding a time at which the toner image forming section starts formation of the toner image, after a toner storage section that stores a toner is replaced. The performing unit performs formation of the toner image by the toner image forming section, in accordance with the selected condition.

In a constitution in which developer feeding power of a first feeding screw 25 in a region opposing a discharge opening 40 for permitting discharge of a developer, the discharge of the developer is properly made.

A blade of the first feeding screw 25 is cut away in a first region including a portion opposing the discharge opening 40. By this, the developer feeding power in the first region is lower than the developer feeding power in a second region adjacent to the first region. A humidity detecting portion as an acquiring portion detects a developer humidity as information on a charge amount of the developer. On the basis of a developer humidity H detected by the humidity detecting portion, a CPU as a control means effects control so that a driving speed at which feeding screws 25 and 26 are driven is faster when the developer humidity is a second humidity higher than a first humidity than when the developer humidity is the first humidity.

A developing device includes a developer holder that holds a developer containing toner and carrier and being supplied to an image holder forming an electrostatic latent image; and a conveyance section that agitates and conveys the developer flowing in from an inlet using a rotation member to cause the developer to flow out toward the developer holder at an outlet, that includes, as a part constituting a portion of the rotation member, a first blade part for conveyance to the outlet and a second blade part for conveyance in a direction opposite to the outlet, and in which a greater amount of the developer flows in from the inlet than the developer flows out from the outlet.

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.

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 development container, a first conveyance member, a second conveyance member, and a developer carrier. The second conveyance member includes a regulation blade that is formed downstream of a second conveyance blade with respect to a second direction which is a conveyance direction of the developer, and that conveys the developer in a direction opposite to the second conveyance blade. A developer replenishment port is formed in an upper surface of the development container, and at least part of an opening length thereof in the second direction is included in a regulation area which is an area inside a second conveyance chamber where the regulation blade is disposed. At least part of the developer replenished through the developer replenishment port falls into both a first conveyance chamber and the regulation area.

A development device includes a development container having a first conveyance chamber and a second conveyance chamber above it, first and second stirring conveyance members that stir developer in the first and second conveyance chambers and convey it in the opposite directions, a developer carrying member that carries on its surface the developer in the second conveyance chamber, and a regulation blade. Feeding of the developer to the developer carrying member and collection of the developer from the developer carrying member are performed in the second conveyance chamber. A horizontal straight line L1 through the center of the rotation shaft of the second stirring conveyance member is above a horizontal straight line L2 through the center of the rotation shaft of the developer carrying member and the straight line L2 is above a horizontal straight line L3 through the center of the rotation shaft of the first stirring conveyance member.

A development device includes a developer container having a first conveyance chamber and a second conveyance chamber above it, a first stirring-conveyance member, a second stirring-conveyance member, a developer carrying member, and a regulation blade. The developer carrying member includes a magnetic member having a regulation pole, a main pole, a release pole, and an attracting pole. A release start position at which the magnetic force of the release pole becomes 5 [mT] or less is below a straight line L1 horizontally passing through the center of a rotation shaft of the second stirring-conveyance member and when the central angle of a developer releasing region where the magnetic force between the release pole and the attracting pole is 5 [mT] or less is represented by X [] and the peak magnetic force of the attracting pole is represented by Y [mT], Y2.1X32.7 is satisfied.

A developing device includes a conveying member to circulate a developer in a housing, a developer discharge portion extending from one end portion of the housing to form a passage through which surplus developer is discharged from the housing, and a discharge regulation member located on an upstream side of the developer discharge portion with respect to a direction in which the developer is conveyed to the developer discharge portion by the conveying member to partially block a conveying path of the developer. The discharge regulation member includes a lower end portion and an upper end portion arranged apart from a bottom and an upper wall of the conveying path, respectively.