Abstract: An image forming apparatus includes a latent-image bearing body, a charging unit, a latent-image writing unit, a development unit, a development power, and a bias control unit. After a start of an image forming operation, the bias control unit performs a process of constantly maintaining an output of a development bias at an adjustment bias value. The adjustment bias value is a central value in a periodic fluctuation range of the output of the development bias. At a timing at which a difference of the development bias from the adjustment bias value in the periodic fluctuation range is less than or equal to a predetermined threshold value, the bias control unit performs switching from the process of constantly maintaining the output of the development bias at the adjustment bias value to a process of periodically changing the output of the development bias based on development bias control data.

Abstract: An image forming apparatus includes a rotatable image carrier that carries a toner image having a length corresponding to at least a circumferential length of the carrier; an image density detector that detects a density of the image; a potential detector that detects, over at least the circumferential length, a surface potential of the carrier before toner adheres thereto; a first image forming device that adjusts the density with a first factor, and forms an image based on a first condition of the first factor; a second image forming device that adjusts the density with a second factor, and forms an image based on a second condition of the second factor; a first determining device that determines the first condition based on uneven density; and a second determining device that determines the second condition based on uneven density and a potential distribution of the surface potential.

Abstract: In an embodiment, a diffuse reflection output conversion method is executed in an apparatus detecting a plurality of gradation patterns. The apparatus includes a light emitter and light receiver, and detects specular reflection and diffuse reflection simultaneously. A region before specular reflection saturation is a region where the specular reflection component decreases and saturates at minimum level. A diffuse reflection detector is calibrated by: obtaining a diffuse reflection output resulting from an amount of attached powder at a border between the region before specular reflection saturation and the region after specular reflection saturation; calculating a ratio between the diffuse reflection output and a reference diffuse reflection output calculated in advance as a calibration coefficient; and multiplying a diffuse reflection output obtained from the gradation patterns by the calibration coefficient calculated at the calculating.

Abstract: An image forming apparatus includes an image carrier; an image forming unit; a processor for controlling the image forming unit according to a predetermined image forming condition setting data; an image density sensor to detect an image density of the toner pattern formed on the image carrier; a reference rotary position detector; an image density fluctuation data acquisition unit to obtain an image density fluctuation data of more than one circumferential length of the photoreceptor drum with reference to the reference rotary position detected by the reference rotary position detector based on a result related to the toner pattern formed on the image carrier detected by the image density sensor; and a correction data generator to generate a correction data to correct a reference image forming condition setting data with a correction amount corresponding to each rotary position of the rotary member to thus reduce the image density fluctuation.

Abstract: An image forming apparatus includes an image carrier, a rotation-position detector, a development device, a transfer unit, a density sensor, and an image-forming-condition determination unit. The density sensor senses a density of a toner image on a transfer body. The image-forming-condition determination unit forms an image pattern, acquires periodical density variation information sensed by the density sensor and detection information of the rotation-position detector, and determines an image forming condition based on the periodical density variation information and the detection information acquired. The image carrier and the transfer body are different in linear velocity in an image formation in which the toner image is transferred to a recording medium.

Abstract: An image forming apparatus includes a latent-image bearing body, a charging unit, a latent-image writing unit, a development unit, a development power, and a bias control unit. After a start of an image forming operation, the bias control unit performs a process of constantly maintaining an output of a development bias at an adjustment bias value. The adjustment bias value is a central value in a periodic fluctuation range of the output of the development bias. At a timing at which a difference of the development bias from the adjustment bias value in the periodic fluctuation range is less than or equal to a predetermined threshold value, the bias control unit performs switching from the process of constantly maintaining the output of the development bias at the adjustment bias value to a process of periodically changing the output of the development bias based on development bias control data.

Abstract: An image forming apparatus includes an image density detector, an image forming device, a rotator, an image density controller, and a timing correction data obtainer. The image density detector detects a toner density of an image formed on an image bearing member. An image forming device forms the image using a density adjustable element that adjusts the density of the image. The rotator forms an image pattern while the density adjustable element is changed, and a density thereof is detected by the image density detector. The image density controller controls the image forming device using a density correction data for the density adjustable element corresponding to a rotational period of the rotator. The timing correction data obtainer obtains timing correction data for correction of driving timing of the image forming device based on a change in the density of the image pattern detected by the image density detector.

Abstract: A rotatable connector device includes a fixed-side member which is to be fixed, and a rotatable-side member which is relatively rotatably attached to the fixed-side member. The rotatable-side member receives a rotation input. The rotatable connector device have a fixed-side cable end accommodation section, projecting from an outer circumferential surface of the fixed-side member in a tangential direction thereof, for accommodating and holding a terminal conductor connection section provided at an end of a flat cable accommodated in the rotatable connector device. The flat cable has a bent portion, in a portion thereof on a side of the terminal conductor connection section, for bending the flat cable so as to shift the portion on the side of the terminal conductor connection section in a width direction of the flat cable.

Abstract: An image forming apparatus includes an image carrier; a developing device; a transfer device; and a fixing device. An electrostatic latent image formed on the image carrier is rendered visible as a toner image by depositing the toner by the developing device, and the toner image is transferred by the transfer device and fixed onto a recording medium by the fixing device and output. The apparatus further includes a density fluctuation meter including a rotary position detector, a density fluctuation detector, and a density fluctuation storage; a density fluctuation extractor unit including a first extractor, a second extractor, and a density fluctuation storage; and a control table generator unit including a control table generator and a control table storage, so that based on the control table stored in the control table storage, the voltage to be applied to the developing device is controlled and the toner image is output.

Abstract: A developing device for developing an electrostatic latent image on an image bearing member including a developer bearing member opposed to the image bearing member to bear thereon a developer including a toner and a magnetic carrier; a developer containing part to contain the developer to supply the developer to the developer bearing member; an agitating or feeding member to agitate or feed the developer in the developer containing part; a magnetic permeability sensor to measure magnetic permeability of the developer to determine toner concentration of the developer; a developer feeder; a feeding member to feed the developer to the developer containing part through the developer feeder; and a driver to drive the feeding member independently of the agitating or feeding member. The magnetic permeability sensor is arranged on the developer feeder.

Abstract: A toner-image detecting sensor for detecting a toner image before being transferred onto a recording sheet and a fixed-image detecting sensor for detecting the toner image after being secondarily transferred and fixed on the recording sheet are arranged so that the positions of them in a main scanning corresponding direction are aligned. An image forming apparatus has a first image adjustment mode and a second image adjustment mode. In the first image adjustment mode, image adjustment is made on the basis of only a result of detection by the toner-image detecting sensor without transferring the test pattern onto the recording sheet. In the second image adjustment mode, the test pattern is transferred onto the recording sheet, and image adjustment is made on the basis of both a result of detection by the toner-image detecting sensor and a result of detection by the fixed-image detecting sensor.

Abstract: A rotatable connector device has a rotator including a ring-shaped rotatable-side ring plate and an inner cylindrical section having a cylindrical shape and formed along an inner circumferential edge of the rotatable-side ring plate, and a stator including a ring-shaped fixed-side ring plate and an outer cylindrical section having a cylindrical shape and formed along an outer circumferential edge of the ring-shaped fixed-side ring plate. The rotator and the stator are engaged with each other, so as to be pivotable with respect to each other with a gap being provided between the rotatable-side ring plate and the outer cylindrical section. An accommodation section, defined by the rotatable-side ring plate and the inner cylindrical section of the rotator and the fixed-side ring plate and the outer cylindrical section of the stator, accommodates a cable for electrically connecting the rotator and the stator to each.

Abstract: There is provided an image forming apparatus that performs gradation correction, including a pattern forming unit that forms, on an image carrier, rows of area coverage modulation patterns having patterns of different gradation values in steps by area coverage modulation method; a toner adhering amount detecting unit that measures toner adhering amount of each pattern of the rows of area coverage modulation patterns formed by the pattern forming unit, the gradation correction being performed based on a detection result of the toner adhering amount detecting unit; and a pattern type selecting unit that selects a single pattern type formed on the image carrier from a plurality of pattern types, when carrying out gradation correction control by forming the rows of the area coverage modulation.

Abstract: An image forming apparatus includes an image forming unit including rotary members to form a toner image corresponding to image data, in which the image forming unit forms a toner pattern for detecting image density fluctuation; and an image forming condition determination controller to perform image forming processing to ultimately transfer the toner image onto a recording medium. In the image forming apparatus, the controller measures a periodic image density fluctuation occurring in a rotation cycle of the rotary members based on a detection result of a toner pattern; performs image forming condition determination processing to determine an image forming condition to reduce the image density fluctuation based on measured image density fluctuation data; and determines whether or not the image density fluctuation data measured multiple times satisfies a predetermined control termination condition.

Abstract: An image forming apparatus includes a duplex conveyance path where a recording medium can be reversed and re-fed; and an output image detector to detect an image or a test pattern formed on a surface of the recording medium. The image forming apparatus is configured to: detect the test pattern formed on the first side of the recording medium by the output image detector; adjust and correct image forming conditions based on the detection result of the detector; convey the recording medium the first side of which the test pattern is formed on, to a duplex conveyance path; re-feed the recording medium and form a test pattern for verifying correction effect on a backside of the recording medium after correcting and updating the image forming conditions; and detect the test pattern formed on the backside of the recording medium again by the output image detector, thereby verifying the correction effect.

Abstract: A fixed-side ring plate rotation regulation section is provided at an outer circumferential edge of a fixed-side ring plate, and an outer cylinder rotation regulation section is provided at an outer circumferential edge of an outer cylinder at a position corresponding to the fixed-side ring plate rotation regulation section. The fixed-side ring plate and the outer cylinder formed of different members from each other are fit to each other such that the fixed-side ring plate rotation regulation section and the outer cylinder rotation regulation section are in contact with each other so as not to rotate about a rotation axis thereof.

Abstract: An image forming apparatus includes a rotatable image carrier that carries a toner image having a length corresponding to at least a circumferential length of the carrier; an image density detector that detects a density of the image; a potential detector that detects, over at least the circumferential length, a surface potential of the carrier before toner adheres thereto; a first image forming device that adjusts the density with a first factor, and forms an image based on a first condition of the first factor; a second image forming device that adjusts the density with a second factor, and forms an image based on a second condition of the second factor; a first determining device that determines the first condition based on uneven density; and a second determining device that determines the second condition based on uneven density and a potential distribution of the surface potential.

Abstract: An image forming apparatus includes an image carrier; a developer carrier configured to adhere toner onto the image carrier; an image density detector to detect a density of an image on the image carrier formed by the developer carrier adhering the toner on the image carrier; a rotary member to form an image pattern of which density is detected by the image density detector; and a rotational position detector to detect a rotational position of the rotary member. In the image forming apparatus, the image pattern is generated based on the rotational position detected by the rotational position detector and the rotary member that the rotational position detector detects the rotational position thereof is either the image carrier or the developer carrier.

Abstract: An image forming apparatus includes plural toner adhered amount detectors that detect an amount of toner particles adhered to the toner image on the image bearer and an image density controller to form a gradation pattern by sequentially arranging plural toner patches in the sub-scanning direction on the image bearer from the least toner adhered amount patch. These toner patches bear a different amount of toner particles from each other. The plural toner patches are detected by the plural toner adhered amount detectors, and the image density controller adjusts an image formation condition for the image formation device based on detection values thereof. These toner adhered amount detectors are symmetrically aligned in a main scanning direction above the image bearer. The image density controller forms the plural toner patches being staggered at different positions on the image bearer, facing these toner adhered amount detectors, respectively.

Abstract: In an image forming apparatus, a processor generates a first density variation data based on the surface potential of the pattern in relation to the rotational position of the image bearer and a second density variation data based on the first density variation data and the density of the toner pattern, stores the first density variation data and the second density variation data in a memory, makes a pattern in a predetermined timing, decides whether the first density variation data is changed or not, change the first density variation data based on the decision, controls the toner image forming condition of the toner image forming device based on the first density variation data and the second density variation data.