Abstract: An imaging system includes a stirring device to stir a developer, a rotatable developer carrier to carry the developer a non-magnetic regulator, a secondary regulator, an excess developer conveyance path extending from the developer carrier and between the non-magnetic regulator and the secondary regulator, a toner supply path to supply a toner to the stirring device, and a merging portion where the toner supply path and the excess developer conveyance path merge. The non-magnetic regulator and the secondary regulator regulate the thickness of the developer carried by the developer carrier. Excess developer from the developer carrier is conveyed via the excess developer conveyance path. The merging region controls the supply of the toner from the toner supply path to the stirring device based, at least in part, on an amount of the excess developer received from the excess developer conveyance path.

Abstract: A developing device includes a casing containing a housing chamber and having a developer outlet port to discharge excess developer from the housing chamber. A developer roll is disposed in the housing chamber, to carry a developer. The developing device includes an airflow passage to allow air to flow in from the housing chamber when the developer roll rotates. The developing device further includes a radiation member located adjacent the housing chamber to transfer heat to the air flowing through the airflow passage.

Abstract: A developing device includes a latent image carrier to form an electrostatic latent image is formed on a surface of the latent image carrier, a developing agent carrier to carry a developing agent including toner on a surface of the developing agent carrier, the developing agent carrier facing the latent image carrier, and a roll-shaped member facing the developing agent carrier to form a first gap and facing the latent image carrier to form a second gap, to form a suction air flow through the first gap and the second gap, to suction toner particles scattered to the first gap between the roll-shaped member and the developing agent carrier and the second gap between the roll-shaped member and the latent image carrier.

Abstract: A developing device includes a casing containing a housing chamber and having a developer outlet port to discharge excess developer from the housing chamber. A developer roll is disposed in the housing chamber, to carry a developer. The developing device includes an airflow passage to allow air to flow in from the housing chamber when the developer roll rotates. The developing device further includes a radiation member located adjacent the housing chamber to transfer heat to the air flowing through the airflow passage.

Abstract: A developing device includes a latent image carrier to form an electrostatic latent image is formed on a surface of the latent image carrier, a developing agent carrier to carry a developing agent including toner on a surface of the developing agent carrier, the developing agent carrier facing the latent image carrier, and a roll-shaped member facing the developing agent carrier to form a first gap and facing the latent image carrier to form a second gap, to form a suction air flow through the first gap and the second gap, to suction toner particles scattered to the first gap between the roll-shaped member and the developing agent carrier and the second gap between the roll-shaped member and the latent image carrier.

Abstract: A developing apparatus including a layer thickness adjustment member configured to regulate a layer thickness of a two-component developer carried on a surface of a developing sleeve of a developing roller is disposed so that one end portion in a width direction faces the surface of the developing sleeve at a predetermined interval. At two end portions in a longitudinal direction of the layer thickness adjustment member, a notch open to the one end side in the width direction is provided. Since an amount of conveyance of the developer locally increases at two end portions of the developing sleeve by providing such a notch in the layer thickness adjustment member, density of an ear of a magnetic brush to be formed increases, and it is possible to exhibit the sufficient seal performance and prevent the toner from being scattered.

Abstract: A developing apparatus including a layer thickness adjustment member configured to regulate a layer thickness of a two-component developer carried on a surface of a developing sleeve of a developing roller is disposed so that one end portion in a width direction faces the surface of the developing sleeve at a predetermined interval. At two end portions in a longitudinal direction of the layer thickness adjustment member, a notch open to the one end side in the width direction is provided. Since an amount of conveyance of the developer locally increases at two end portions of the developing sleeve by providing such a notch in the layer thickness adjustment member, density of an ear of a magnetic brush to be formed increases, and it is possible to exhibit the sufficient seal performance and prevent the toner from being scattered.

Abstract: An image forming apparatus includes: a developing device having a developing vessel, a developing roller and a toner supply port; a toner supply device; a toner supply detecting sensor for detecting the toner concentration inside the developing vessel; a toner concentration controller for directing toner supply; a toner empty detector; and a sheet conveyance detecting sensor. The toner concentration controller has a toner supply device control function; and a toner supply stopping function of stopping toner supply when the last sheet of image printout being executed has passed by the predetermined position in the sheet conveyance path.

Abstract: Provided are an image forming apparatus that, when a difference between a developing bias in correcting an image density and a reference developing bias has a value not less than a prescribed value that is set preliminarily, replenishes or consumes a toner forcibly, executes correction of the image density again, and controls the developing bias in such a manner that a toner density is controlled to fall within an appropriate range, and an image forming method using the same. When a difference between a developing bias value after correction of the image density and the reference developing bias becomes larger than the prescribed value to the plus side or the minus side, a toner density control portion performs control to consume or replenish a toner forcibly.

Abstract: An image forming apparatus includes: a developing device; a toner supply device; and a toner supply detecting sensor; and a toner concentration controller that directs toner supply. The toner concentration controller includes: a memory that stores the difference between the outputs from toner supply detecting sensor before and after toner supply; a toner supply quantity determinater that determines that the amount of toner remaining in the toner supply device is low and the amount of toner supply is low when the output difference or output ratio of the sensor is lower than a supply reference value; and an image quality adjustment controller that shortens the interval of time between adjustment of electrical potential on toner concentration correction in the above case.

Abstract: An image forming apparatus includes a developing device having a toner supply sensor, a toner supply device supplying toner to the developing device, a toner supply controller controlling toner supply from the toner supply device to the developing device based on predetermined conditions, a toner empty determiner determining whether toner is present inside the toner supply device. In the image forming apparatus, the toner supply device includes a storage for recording multiple measured values of toner supply detected by the toner supply sensor, and the toner supply controller corrects the amount of toner supply, based on the moving average of multiple measured values of the amount of toner supply.

Abstract: A developing device includes a developing vessel, first and second conveying passages for conveying a developer, first and second conveying members for agitating and conveying the developer, a developing roller, a toner supply port for receiving a supply of toner and an agitator arranged under the toner supply port. The first conveying member has a rotary shaft and first and second conveying blades formed on the periphery of the rotary shaft. The agitator is arranged coaxially with the first conveying member so as to be rotatable independently from the first conveying member. The agitator includes a circular helical blade formed around the outer periphery of the second helical blade.

Abstract: A developing device conveys a two-component developer on a first route of circulation and a second route of circulation, and includes a guide plate and an electromagnet that are used for choosing, in accordance with toner densities detected by two toner density detecting sensors respectively provided in the two routes, whether toner supplied from a toner supply device is guided into the first or second route of circulation. This makes it possible to provide an image forming apparatus that, even in cases where a large amount of toner is consumed at one end of a developing roller along the axial direction in a developing device provided with one toner supply opening, can form an image free from nonuniformity in image density or photographic fogs that are caused by nonuniformity in toner density of a two-component developer.

Abstract: The change in an output voltage when a control voltage is changed is calculated, and the change in the control voltage divided by the calculated change in the output voltage is defined as a sensitivity coefficient. The sensitivity coefficient is recalculated for each predetermined time interval or whenever a predetermined condition is satisfied, and the control voltage is corrected based on the recalculated sensitivity coefficient. Example of the predetermined condition include the time of start-up of the apparatus, the time at which the accumulated number of printed sheets reaches a predetermined number, and the time of carrying out process control.

Abstract: To provide a developing device, which includes: a first conveying passage through which a developer including a toner and a magnetic carrier is conveyed; a first conveying member disposed in the first conveying passage for conveying the developer in a predetermined whilst agitating; a toner supply port for supplying toner into the first conveying passage; and a multiple number of electromagnets arranged in the upper part of the first conveying passage and on the downstream side of the toner supply port with respect to the developer's direction of conveyance for creating magnetic fields inside the first conveying passage along the developer's direction of conveyance, and which can improve agitation performance and conveying performance of the developer without extremely increasing stress acting on the developer, as well as providing an image forming apparatus and developer conveying method using the device.

Abstract: Provided are an image forming apparatus that, when a difference between a developing bias in correcting an image density and a reference developing bias has a value not less than a prescribed value that is set preliminarily, replenishes or consumes a toner forcibly, executes correction of the image density again, and controls the developing bias in such a manner that a toner density is controlled to fall within an appropriate range, and an image forming method using the same. When a difference between a developing bias value after correction of the image density and the reference developing bias becomes larger than the prescribed value to the plus side or the minus side, a toner density control portion performs control to consume or replenish a toner forcibly.

Abstract: A toner carrying device includes a flexible sheet, and a sheet moving mechanism for allowing the flexible sheet to move back and forth by pulling the flexible sheet. In the flexible sheet, a toner passage hole for leaving a first opening section of a toner carrying pipe to open is provided. In a case where the toner passage hole is divided into first through three areas in such a manner that (i) the first area is provided on a side of one end of the flexible sheet in a direction orthogonal to a moving direction of the flexible sheet; (ii) the second area is provided on a side of the other end of the flexible sheet in the direction orthogonal to the moving direction; and (iii) the third area is provided between the first area and the second area, the third area extends broader in the moving direction than respective of the first and second areas. This allows the flexible sheet partially having the toner passage hole in its area to move smoothly.

Abstract: An image forming apparatus includes: a developing device having a developing vessel, a developing roller and a toner supply port; a toner supply device; a toner supply detecting sensor for detecting the toner concentration inside the developing vessel; a toner concentration controller for directing toner supply; a toner empty detector; and a sheet conveyance detecting sensor. The toner concentration controller has a toner supply device control function; and a toner supply stopping function of stopping toner supply when the last sheet of image printout being executed has passed by the predetermined position in the sheet conveyance path.

Abstract: An image forming apparatus includes: a developing device; a toner supply device; and a toner supply detecting sensor; and a toner concentration controller that directs toner supply. The toner concentration controller includes: a memory that stores the difference between the outputs from toner supply detecting sensor before and after toner supply; a toner supply quantity determinater that determines that the amount of toner remaining in the toner supply device is low and the amount of toner supply is low when the output difference or output ratio of the sensor is lower than a supply reference value; and an image quality adjustment controller that shortens the interval of time between adjustment of electrical potential on toner concentration correction in the above case.

Abstract: In an image forming apparatus comprising a charging section, an exposure section, a developing section, a transfer section, a peeling section, a cleaning section including a cleaning blade, and a fixing section, the cleaning blade is composed by dispersing 15 parts by weight through 33 parts by weight of fluorine resin particulate and secondary particles thereof into 100 parts by weight of a synthetic resin of a base material and, on a surface of the cleaning blade 16a, and a number of the secondary particles of the fluorine resin particulate having a particle diameter of 0.5 ?m or more existing in unit area of 100 ?m2 is made to be 50 or less.