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 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: 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: 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: 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-information acquiring unit acquires the image information divided at least in one of a main-scanning direction and a sub-scanning direction. A supply control unit calculates basic-supply patterns of a supply amount of toner and controls the supply amount at a supply point in a developing unit using a toner supply pattern combined with the basic-supply patterns that eliminate temporal variation in toner density of the developer, at the specific point, due to development of the latent image.

Abstract: In an image forming apparatus, a first controller forms a first image pattern on an image bearer and determines a first image formation condition based on a detection result of density of a toner image. The first controller then controls a toner image forming device based on the first image formation condition. A second controller forms a second image pattern different from the first image pattern on an image bearer and determines a second image formation condition based on a detection result of density of a toner image. The second controller then controls a toner image forming device based on the second image formation condition.

Abstract: An image forming apparatus forms a plurality of tone patterns of different colors, each of which containing a plurality of toner patches having different toner densities. Some of the toner patches in each of the tone patterns are formed with a predetermined fixed developing bias and the rest of the toner patches in each of the tone patterns are formed with developing biases set based on previous developing biases that have been obtained through a previous control process. The largest toner density of the toner patches in each of the tone patterns is determined based on a magnitude relation of previous index values obtained through the previous control process.

Abstract: An image forming apparatus is provided. The image forming apparatus includes an acquiring unit that acquires a plurality of types of operation control information of the image forming apparatus that indicate deterioration of a toner in the image forming apparatus or deterioration of a component of the image forming apparatus. An index value calculating unit calculates an index value indicating a state of the image forming apparatus based on the acquired operation control information. An abnormality judging unit judges whether the image forming apparatus abnormality has occurred and predicts an occurrence of a failure that requires maintenance of the image forming apparatus due to deterioration of the toner in the image forming apparatus or deterioration of the component of the image forming apparatus based on the index value.

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: An image forming apparatus is provided which is of an electrophotographic type, and is capable of setting a gradation number of a patch pattern to be formed corresponding to various factor information, and to perform a process control. The image forming apparatus includes a patch pattern forming part to form a toner image of a patch pattern on an image carrier; a developing part to develop the patch pattern; a toner image density detecting part to measure a toner image density of the patch pattern; and a process control performing part to vary an image forming process condition based on detection results obtained from the toner image density detecting part, and to stabilize an image density.

Abstract: An image forming apparatus includes an image forming unit configured to form a plurality of toner images on an image carrier, an optical detector configured to detect reflection light from the toner image, and dedicated to detect infrared rays and near-infrared rays, and a controller configured to perform a predetermined control using a detection results of the optical detector. Gradation pattern that is comprised of a plurality of toner patches formed in the image forming unit with an image forming condition to have different adhesive amounts, and is formed of at least two colors, and detection values detected by the optical detector are used for the predetermined control.

Abstract: An image forming apparatus and an image density control method for controlling image density in the image forming apparatus, involving adjusting a toner concentration control reference value in accordance with an amount of the toner replaced in a developing device so as to adjust the image density to maintain a consistent developability and changing image forming intervals in accordance with an amount of the toner replaced in the developing device during continuous printing operation.

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: An image forming apparatus is provided. The image forming apparatus includes an acquiring unit that acquires a plurality of types of operation control information of the image forming apparatus that indicate deterioration of a toner in the image forming apparatus or deterioration of a component of the image forming apparatus. An index value calculating unit calculates an index value indicating a state of the image forming apparatus based on the acquired operation control information. An abnormality judging unit judges whether the image forming apparatus abnormality has occurred and predicts an occurrence of a failure that requires maintenance of the image forming apparatus due to deterioration of the toner in the image forming apparatus or deterioration of the component of the image forming apparatus based on the index value.

Abstract: An image forming apparatus is provided. The image forming apparatus includes an acquiring unit that acquires a plurality of types of operation control information of the image forming apparatus that indicate deterioration of a toner in the image forming apparatus or deterioration of a component of the image forming apparatus. An index value calculating unit calculates an index value indicating a state of the image forming apparatus based on the acquired operation control information. An abnormality judging unit judges whether the image forming apparatus abnormality has occurred and predicts an occurrence of a failure that requires maintenance of the image forming apparatus due to deterioration of the toner in the image forming apparatus or deterioration of the component of the image forming apparatus based on the index value.

Abstract: An image forming apparatus includes an image carrier configured to carry an electrostatic latent image, a developing device configured to develop the electrostatic latent image with a two-component developer including toner and magnetic carrier, a toner supplier configured to supply the toner to the developing device, a toner concentration detector configured to detect toner concentration in the two-component developer inside the developing device, and a controller. The controller is configured to detect first information to determine toner replacement amount in the developing device during a predetermined time period and second information to determine a charge characteristic of the toner in the developing device, change a toner concentration control reference value based on the first information and the second information, and control the toner concentration based on an output from the toner concentration detector and the toner concentration control reference value.

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: 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: An abnormality determining apparatus includes an information storing device that stores information, an information obtaining device that obtains information of a detection subject, a receiving device that receives abnormality presence/absence information indicative of the presence or absence of an abnormality in the detection subject detected by a user, a normal group data set constructing device that constructs a normal group data set that is a collection of normal data indicating that the detection subject is in a normal state based on the abnormality presence/absence information received by the receiving device and based on the information obtained by the information obtaining device during a preset period, and a determining device that determines the presence or absence of an abnormality in the detection subject by performing calculations based on the normal group data set stored in the information storing device and based on the information obtained by the information obtaining device.