Abstract: A developing device includes a developing container, a first agitating feeding member, a second agitating feeding member, a first developer delivery portion, a second developer delivery portion, and a toner sensor. The developing container includes a first transport path and a second transport path. The first agitating feeding member and the second agitating feeding member agitate and feed developer. The first developer delivery portion delivers the developer from the first transport path to the second transport path. The second developer delivery portion delivers the developer from the second transport path to the first transport path. The toner sensor is disposed at a part of the first transport path near the first developer delivery portion. A ceiling height of a part of the first transport path facing the first developer delivery portion is larger than a ceiling height of other part of the first transport path.

Abstract: A developing device of the present disclosure has a developer bearing member, a toner bearing member, a bias controller. With respect to a duty ratio of the alternating current bias of a polarity with which the toner is moved from the developer bearing member to the toner bearing member, a second duty ratio that is a duty ratio of the collection bias is set to be smaller than a first duty ratio that is a duty ratio of the development bias. When a transition is made from the development operation to the collection operation, in a state where the developer bearing member and the toner bearing member are being driven to rotate, the bias controller performs control so that the bias applier applies the alternating current bias having a third duty ratio that is smaller than the first duty ratio and larger than the second duty ratio.

Abstract: An image forming apparatus includes an image bearing member, a developing unit, a cleaning unit, and a heating element. The heating element for heating the image bearing member includes: a substrate having a length corresponding to an entire region of the image bearing member in a longitudinal direction of the image bearing member; and a plurality of resistor chips mounted on the substrate. At least either resistance values or spacing intervals of the resistor chips vary in a longitudinal direction of the substrate to ensure that the surface temperature distribution of the image bearing member heated by the heating element is uniform.

Abstract: An image forming apparatus includes a heating element, an interior temperature/humidity detection section, and a controller. The heating element is conducted during connection of the image forming apparatus to an external power source to heat an image bearing member. The interior temperature/humidity detection section detects temperature and humidity in the interior of the image forming apparatus. The controller performs a refresh operation when a relative humidity calculated on the basis of the temperature and humidity detected by the interior temperature/humidity detection section immediately after the image forming apparatus is connected to the external power source is higher than the preset value. The refresh operation is an operation for supply of developer from a development device to the image bearing member and for polish of the surface of the image bearing member with the use of a polishing member.

Abstract: An image forming apparatus includes an image bearing member, a charging unit, a laser scanning unit, a developing unit, a transfer member, a recording medium conveyance path, a cleaning unit, and a heating element. The recording medium conveyance path includes a resin member that forms a conveyance surface. The resin member has a concave portion at a location closer to the transfer member than to the image bearing member. The heating element for heating the image bearing member is accommodated in the concave portion. The heating element is disposed downstream from the contact point between the image bearing member and the transfer member in the conveyance direction in which a recording medium is conveyed through the recording medium conveyance path. The developing unit is located upstream from the contact point between the image bearing member and the transfer member in the conveyance direction of the recording medium.

Abstract: A developing device of the present disclosure has a developer bearing member, a toner bearing member, a bias controller. With respect to a duty ratio of the alternating current bias of a polarity with which the toner is moved from the developer bearing member to the toner bearing member, a second duty ratio that is a duty ratio of the collection bias is set to be smaller than a first duty ratio that is a duty ratio of the development bias. When a transition is made from the development operation to the collection operation, in a state where the developer bearing member and the toner bearing member are being driven to rotate, the bias controller performs control so that the bias applier applies the alternating current bias having a third duty ratio that is smaller than the first duty ratio and larger than the second duty ratio.

Abstract: The present invention relates to a developing device for developing images formed on an image carrier. The device is capable of regulating toner amount such that the amount of toner conveyed by the toner control to the developing area is reduced, as well a appropriately changing the carrier.

Abstract: The present invention relates to a developing device for developing images formed on an image carrier comprising: a rotatably mounted roller-like toner carrier for holding a toner on the surface thereof; a plate-like regulating member for regulating an amount of the toner held on the toner carrier, the regulating member having at least one bent part, a first regulating part that is located such that it is in contact with the toner carrier and a second regulating part that is located such that it is in contact with the toner carrier at downstream side of the first regulating part with respect to the surface-moving direction of the toner carrier; and a casing for accommodating the toner, the toner carrier and the regulating member; wherein the regulating member is positioned between the toner carrier and the casing.

Abstract: A developing apparatus with a developing roller for conveying toners held on its surface to a developing area opposite to an image carrying member, the surface of the developing roller being moved upward from below in the developing area; a regulating member for regulating an amount of the toners to be conveyed to the developing area by the developing roller; a plate-shaped charging member for charging the toners; and a voltage applying device for applying a voltage to the charging member.

Abstract: A development apparatus according to the invention comprises at least two developer carrier members in juxtaposition for transporting a developer material to a development region between the developer carrier members and an image bearing member in opposed relation. An AC voltage applying device is adapted to apply AC voltages to the respective developer carrier members thereby applying AC electric fields to the respective gaps between the developer carrier members and the image bearing member based on an active period to apply the AC electric field and an inactive period to apply no AC electric field. When one of the adjacent developer carrier members is subject to the active period, the other developer carrier member is subject to the inactive period.

Abstract: A developing device is provided with a magnetic member having a plurality of magnetic poles N and S within a developing sleeve that rotates to transport a developer to an image bearing member. The device also includes a regulating member, which is formed of magnetic material, and which is spaced from the developing sleeve in so that the surface of the regulating member that is located on the upstream side in the developer transport direction is positioned downstream in the developer transport direction from a point of peak perpendicular magnetic flux density of the opposing magnetic pole of a magnetic member near the position at which the regulating member faces the developing sleeve, and positioned upstream in the developer transport direction from a point of 1/2 the peak perpendicular magnetic flux density of the opposing magnetic pole.