Abstract: A toner classification apparatus comprising a classification rotor, wherein the classification rotor comprises a first vane group containing first vanes and a second vane group containing second vanes, the second vanes have a length shorter than the first vane group; the number of second vanes, which are disposed between two adjacent first vanes, is 1 to 2, independently; each of the first vanes draws first trajectory and each of the second vanes draws second trajectory when the classification rotor rotates, a distance from the center of rotation to an outer circumference side end of the first and second trajectory are defined as L1 and L3, respectively, and a distance from the center of rotation to the center side end of the first and second trajectory are defined as L2 and L4, respectively, L1 to L4 satisfy prescribed relationships, and a toner production method using the toner classification apparatus.

Abstract: [Problem to be solved] To further develop a prior art cartridge. [Solution] A cartridge includes a holding movable between a first position for stably holding a second unit in a spaced position by a first unit and a second position, and a contact force receiving portion capable of receiving a contact force for moving the holding portion from the first position toward the second position to move the second unit to a developing position, when the second unit is in the spaced position.

Abstract: An image forming apparatus includes a tray which is movable between a housed position at which the tray is housed in a housing portion of a body and a drawn-out position, a first cartridge detachably attached to the tray and including a first developing roller, and a second cartridge detachably attached to the tray and including a second developing roller. In a contacting state where (i) the first cartridge and the second cartridge are attached to the tray, (ii) the tray is in the housed position, (iii) the first developing roller contacts a first photosensitive drum, and (iv) the second developing roller contacts a second photosensitive drum, a position of a first projection of the first cartridge and a position of a first holder to which a first memory is fixed at least partially overlap each other with respect to the vertical direction.

Abstract: Provided are a process cartridge and an electrophotographic apparatus each capable of suppressing an image defect (coarseness in a halftone image) caused by toner scattering in association with a charging failure that occurs when the process speed of the electrophotographic apparatus is further increased. The process cartridge includes: an electrophotographic photosensitive member; and a developing unit, which includes a toner storing portion that stores a toner, and which supplies the toner to a surface of the electrophotographic photosensitive member. The electrophotographic photosensitive member includes a surface protective layer containing an electroconductive particle in an appropriate amount, and the volume resistivity of the surface protective layer is controlled. As the toner, there is used a toner in which an organosilicon polymer is present on the surface of a toner particle, a silanol group is present in part of the organosilicon polymer, and the amount of the silanol group is controlled.

Abstract: In a developing unit, one of a frame body and an end portion member, which sandwich a bearing member rotatably supporting a developing roller in an axis direction of the developing roller, includes a hole portion depressed in the axis direction on a surface facing the bearing member, and the other of the frame body and the end portion member includes a protruding portion inserted into the hole portion. The protruding portion includes a first region that is press-fitted into an inner wall surface of the hole portion, and a second region that faces the inner wall surface with a gap therebetween, and at least the gap is filled with an adhesive via a communication hole that extends in a direction intersecting the rotation axis direction such that the gap leads to an outside of the frame body.

Abstract: A developing device includes a developer carrying member configured to carry a developer, containing toner and a carrier, for developing an electrostatic latent image formed on an image bearing member, a developer container configured to accommodate the developer, and an oscillation circuit including a resonance circuit including a coil and a circuit portion containing a capacitor and configured to oscillate a signal for detecting a toner concentration of the developer accommodated in the developer container. The coil is formed integrally with the developer container by a metal film, and the coil is disposed on an inner wall surface of the developer container.

Abstract: It is an object of the present invention to provide an electrophotographic photosensitive member capable of suppressing the environmental fluctuation in the electrical characteristics. The present invention provides the electrophotographic photosensitive member in which the surface layer contains the compound having the specific structure.

Abstract: An image forming apparatus includes a developer container to and from which a replenishment container is attachable and detachable and which includes an accommodating portion that accommodates developer and a replenishment port, an agitation member, an opening/closing member configured to be movable between a closed position and an open position, a drive source for driving the agitation member, and a control portion configured to control the drive source. The apparatus is configured such that image formation is not possible when the opening/closing member is at the open position, and the agitation member is capable of driving in a case where the opening/closing member is at the open position.

Abstract: A charging member includes a conductive base material; an elastic layer that is provided on the conductive base material and has a storage elastic modulus G of 5.0 MPa or less at 100 Hz; and a surface layer that is provided on the elastic layer, in which in a Cole-Cole plot obtained by measuring the charging member in a range of 1 MHz to 0.1 Hz by an alternating current impedance method, a resistance component Ra of a capacitive semicircle including 2.5 kHz is 6.3×104? or less.

Abstract: An image forming apparatus includes a fixing device and a control unit. The fixing device includes a heating resistor formed of a positive temperature coefficient material. The control unit energizes the heating resistor with a first energization amount if a temperature of the heating resistor is lower than a predetermined temperature, and energizes the heating resistor with a second energization amount that is higher than the first energization amount if the temperature of the heating resistor is higher than the predetermined temperature.

Abstract: In a case where a cleaning member is located at a cleaning position in attachment of a process cartridge to an image forming apparatus, a stopper located at a first position butts against the process cartridge guided in a direction of attachment by a guide portion such that the process cartridge is disabled from being attached to the image forming apparatus, and in a case where the cleaning member is located at a retraction position in attachment of the process cartridge to the image forming apparatus, a lever portion moves due to a press by a cleaning unit and the stopper moves from the first position to a second position such that the process cartridge is enabled to be attached to the image forming apparatus.

Abstract: A process cartridge detachably mountable to a main assembly of an image forming apparatus, the process cartridge includes a photosensitive drum unit including a photosensitive drum, and a first and second positioning portions Configured to position the photosensitive drum unit relative to the main assembly; and a developing unit connected with the photosensitive drum unit, the developing unit including a developing roller, a storing means having a contact surface electrically connectable with a main assembly contact of the main assembly to communicate with the main assembly. As seen in an axial direction of the photosensitive drum, a first line segment connecting the first positioning portion and the second positioning portion with each other and a first linear line passing through the contact surface and perpendicular to the contact surface crosses with each other.

Abstract: A transfer device includes: an endless member in an endless shape that orbits; primary transfer members that are respectively arranged on an opposite side of plural image holding bodies disposed side by side in a circumference direction of the endless member with the endless member interposed between the primary transfer member and the image holding body, and transfer an image held by the image holding body to the endless member; a secondary transfer member that transfers the image transferred to the endless member to a recording medium; an applying roll around which the endless member is wound, that is disposed on a downstream side of all the primary transfer members and on an upstream side of the secondary transfer member in the circumference direction, and that urges the endless member from an inner peripheral surface of the endless member to apply tension to the endless member; an upstream roll around which the endless member is wound, and that is disposed on the downstream side of all the primary transfe

Abstract: An image forming apparatus includes an image bearing member, an image forming portion, a transfer member, an applying portion, and an executing portion configured to execute an output operation for forming and outputting a chart formed on a recording material on which a plurality of test images are transferred by applying a plurality of voltages to the transfer member by the applying portion. The executing portion changes a change width per level of the test voltage so that the change width is a first change width in a case that a material of the recording material on which the chart is formed is a first material and so that the change width is a second change width different from the first change width in a case that the material of the recording material is a second material different from the first material.

Abstract: A conductive sheet capable of preventing erroneous reading and writing is provided. The conductive sheet according to one embodiment is configured to be positioned between a sheet tray of an image forming device and a sheet. The conductive sheet includes a base layer and a double conveyance prevention structure. The base layer comprises a conductive material positioned to overlap with a wireless tag of the sheet. The double conveyance prevention structure is coupled to or defined by the base layer. The double conveyance prevention structure is configured to prevent conveyance of the conductive sheet by the image forming apparatus when the conductive sheet overlaps the sheet in the sheet tray.

Abstract: A fixing device includes a fixing belt, a pressing roller, a flat heater, a heater holder and a pair of mounting members. The flat heater has a first surface coming into contact with an inner circumferential surface of the fixing belt and a second surface opposite to the first surface. The heater holder comes into contact with the second surface of the flat heater. The mounting members comes into contact with both end portions of the first surface of the flat heater in the width direction, and are mounted to the heater holder such that the flat heater is held between the mounting members and the heater holder. The mounting member includes a downstream side end surface contact part which comes into contact with a downstream side end surface of the flat heater in the conveying direction.

Abstract: An optical scanning device includes a plurality of light source units and a casing of the optical scanning device. The plurality of light source units includes a light source and a holder for holding the light source, respectively. The casing includes a plurality of mounting surfaces for holding a cylindrical portion of the holder. Each of the holders includes two projecting portions at one end portion of the holder with respect to a direction of a central axis of the cylindrical portion, perpendicular to the central axis of the cylindrical portion and extending in a direction away from the central axis each other when viewing the light source unit in the axial direction of the central axis, the projecting portions being provided with a U-shaped cut-way portion, respectively.

Abstract: An image forming apparatus includes a conveyance portion, a printing portion, a delay storage portion, a control portion, an input portion, and a display portion. The delay storage portion can store delay information. The control portion performs a measurement mode. The input portion receives instructions to start and end the measurement mode. When an instruction to perform the measurement mode is entered, the control portion deletes the delay information stored in the delay storage portion and stores the delay information generated thereafter during printing in the delay storage portion. When an instruction to end the measurement mode is entered, the control portion displays on the display portion delay information on predetermined irregular delay factors that occur irregularly during printing, out of the delay information stored in the delay storage portion.

Abstract: An image forming system includes an image forming unit for forming an image on a recording medium, a varnish applying unit for applying varnish to the image on the recording medium, and a control unit for controlling the image forming unit to form a first image and a second image and for controlling the varnish applying unit to apply varnish to the first image and the second image such that a first varnish application amount applied to the first image by the varnish applying unit is different from a second varnish application amount applied to the second image by the varnish applying unit.

Abstract: A document reading device includes: a device body; a transport path that is provided in the device body and through which a document is transported; a reading unit that is provided in the device body, has a reading surface, and reads an image of a document transported through the transport path; a moving part that is provided in the device body and is capable of being moved to a covering position at which the moving part covers the reading surface and to an exposing position at which the moving part exposes the reading surface; a first opening and closing part that is provided on the device body so as to be opened and closed and opens the transport path, at a first opening position; and a second opening and closing part that is provided beside the device body so as to be opened and closed or so as to be removable and mountable and exposes the moving part, at a second opening position or a removal position.