Konica Minolta Business Technologies, Inc.

Minolta Company, Ltd.

Konica Minolta, Inc.

Mitsuru Obara

Kazuomi Sakatani

Masaki Tanaka

Soh Hirota

Masahiro Kouzaki

Katsuyuki Hirata

Hironori Akashi

Atsushi Ishikawa

Kenichi Sawada

Toshio Tsuboi

Takashi Harashima

Yoshinori Tsutsumi

Tatsuya Isono

Kanako Kibihara

Kazuhiro Ishiguro

Junji Nishigaki

Tetsuya Sakai

Munenori Nakano

Yusuke Mamiya

Shigeki Naiki

Toshiya Shirasawa

Tomoyuki Saito

An image forming apparatus includes an image carrying member, a charging device that uniformly charges the image carrying member, an exposure device that forms an electrostatic latent image on the image carrying member, a development device that applies a development bias voltage to form a visible image in which toner is adhered to the electrostatic latent image, a control portion that controls an exposure amount in the exposure device and the development bias voltage and a storage portion that stores an exposure condition and a development condition. The resolution of image data can be switched to at least two types, a standard resolution and a high resolution higher than the standard resolution, and when the resolution of the image data is set at the high resolution, the control portion controls the exposure amount in the exposure device to perform thinning processing on the image.

Image forming apparatus

An image forming apparatus having an image carrier; an electrostatic latent image forming device that forms an electrostatic latent image on the image carrier; a development device having a housing section that stores toner therein, a stirring device for stirring the toner inside the housing section, and a toner, carrier that develops the electrostatic latent image into a toner image by imparting the toner to the image carrier; a voltage applying device that applies a development bias voltage between the image carrier and the toner carrier; a control device that makes the electrostatic latent image forming device and the development device form a test toner image on the image carrier; and a sensing device that senses a toner adhering amount of the test toner image. The control device determines whether to make the stirring device stir the toner based upon a relation between the toner adhering amount of the test toner image and the development bias voltage that was applied by the voltage applying device for formation of the test toner image.

An image forming apparatus has an image bearing member that moves at a specified speed; a toner pattern forming section for forming toner patterns of a specified type on the image bearing member under specified image forming conditions; a toner pattern detection member for detecting the toner patterns formed on the image bearing member; a toner amount varying section for varying a target amount of toner to adhere to the toner patterns; and a control section that calculates a toner adherence amount and a toner adherence position from detection results outputted from the toner pattern detection member and that performs image stabilization control to adjust the image forming conditions based on the calculation results. In the image stabilization control, the control section uses detection results of the same toner patterns both to calculate the toner adherence amount and to calculate the toner adherence position.

Image forming apparatus that performs image stabilization control

A color image forming apparatus having photosensitive members; developing devices for developing electrostatic latent images formed on the photosensitive members into toner images with developers comprising toner and carriers; toner concentration sensors for detecting toner concentrations of the developers in the respective developing devices; a toner image bearing member for bearing the toner images temporarily; a toner adherence amount sensor for detecting toner adherence amounts of the toner images held on the image bearing member; and a controller for calculating, with respect to the developing devices, individual optimal developing bias voltage ranges within which a target toner adherence amount can be achieved while the toner concentrations of the developers are within a predetermined toner concentration range from a lower limit to an upper limit, so as to specify a common optimal developing bias voltage range that are commonly suitable for all the developing devices to achieve the target toner adherence amount while the toner concentrations of the developers in the developing devices are within the predetermined toner concentration range, and for calculating target toner concentrations of the developers in the respective developing devices to achieve the target toner adherence amount while a voltage within the common optimal developing bias voltage range is applied between each of the photosensitive members and each of the developing devices.

Color image forming apparatus

The developing apparatus, having stirring members for conveying and stirring developer-tank-contained developer and a developer holder, comprises a developer replenishing tank; a magnetic-type toner concentration detecting sensor; a trickle-type discharging mechanism; conveying state switching device for temporarily blocking the flow of the developer-tank-contained developer and for temporarily switching the circulating state of the developer-tank-contained developer to the staying state thereof; and a controller for controlling replenishment operation for replenishing the toner and the carrier for replenishment to the developer tank when the toner concentration is lower than a predetermined reference toner concentration, wherein the controller determines the amounts of the toner and the carrier to be replenished on the basis of the calculated toner concentration and the estimated amount of the developer.

Image forming device having a trickle developing apparatus

The developing apparatus, having stirring members for conveying and stirring developer-tank-contained developer and a developer holder, comprises a developer replenishing tank; a toner concentration detecting sensor; a trickle-type discharging mechanism; a developer amount estimating sensor; and a controller for controlling replenishment operation for replenishing the toner and the carrier for replenishment to the developer tank when the toner concentration is lower than a predetermined reference toner concentration, wherein the controller determines the amounts of the toner and the carrier to be replenished on the basis of the calculated toner concentration and the estimated amount of the developer.

Developing apparatus and image forming machine

An image forming apparatus includes a secondary transfer roller that becomes a pressed state to make an intermediate transfer belt perform a transfer process and can move between the pressed state and a separated state, a press and separation driving device for driving the secondary transfer roller to become the pressed state and the separated state, a press and separation detecting device for detecting a pressed or separated state, and a voltage applying portion for applying a voltage between the intermediate transfer belt and the secondary transfer roller. The press and separation detecting device includes a resistor for detecting a current and a determination portion for determining a pressed or separated state in accordance with the detected current.

Image forming apparatus and method for detecting separated state of transfer member

An image forming apparatus has a structure in which a toner image formed in an electrophotographic process is transferred from an intermediate transfer belt to a member to be transferred. The apparatus includes a secondary transfer roller that becomes a pressure contact state with respect to the intermediate transfer belt to make it perform a transfer process and can move between the pressure contact state and a separated state, and a press and separation driving device for driving the secondary transfer roller to become the pressure contact state and the separated state. The pressure contact state or the separated state of the secondary transfer roller is detected in accordance with a variation of an output of an IDC sensor for detecting a state of a bare surface of the intermediate transfer belt.

Image forming apparatus and method for detecting separated state of transfer unit

In an image forming apparatus of the present invention, a developing unit for magenta contains magenta-type toner for pseudo full-color image forming whose chromaticity point is shifted closer to yellow hue on a chromaticity diagram, in comparison with genuine-magenta toner for full-color image forming, and likewise, a developing unit for cyan contains cyan-type toner for the pseudo full-color image forming whose chromaticity point is shifted closer to yellow hue on the chromaticity diagram, in comparison with genuine-cyan toner for the full-color image forming.

Image forming apparatus and image forming method

An electrophotographic image forming apparatus includes a developing device including a developer reservoir for accommodating a mixed developer. The mixed developer includes a plurality of types of toner having a generally identical hue and different reflection densities. The apparatus also includes a replenishment device having a plurality of toner containers each accommodating one of the plurality of types of toner for replenishing the plurality of types of toner to the developer reservoir; a first detector for detecting whether each of the toner containers is completely empty of toner; and a second detector for detecting whether the developer reservoir is nearly or completely empty of mixed developer. A controller controls the replenishment device and allows or prohibits a printing operation based on the detection result of the first and the second detectors.

Image forming apparatus and developing unit

An electrophotographic image forming apparatus includes a developer reservoir for accommodating a single-component mixed developer including two types of toner having a generally identical hue and different reflection densities. A magnetic substance is added to one of the two types of toner. The apparatus also includes a detector for detecting a magnetic permeability of the developer in the developer reservoir and a unit for determining a mixture ratio of the two types of toner based on the magnetic permeability of the developer detected by the detector.

Image forming apparatus and a developing apparatus having a unit for determining a mixture ratio of two types of magnetic toner based on magnetic permeability and amount

An image processing system provided with a line sensor for reading image signals in line units. First, the line sensor scans a document in a normal direction. At this time the image data obtained by the scan are subjected to image processing such as compression and the like. Areas of image data that cannot be processed to the high moving speed of the scanner are subjected to image processing by later performing a scan in the reverse direction.

Image processing device and image processing method

A data processing system has the following construction in order to achieve high speed data processing with reduced memory capacity. There are provided a memory to store a plurality of pieces of sequentially input data to be processed, a plurality of processors to execute a series of processings, e.g., Log conversion, MTF correction, gamma correction and binarization in this order to the data to be processed stored in the memory in the order of input, and a state control portion to determine which processing is stagnant by monitoring the progress of a processing by each of said plurality of processors and prohibit a processor executing a processing succeeding to a processing determined as being stagnant from accessing the memory. Processings by the plurality of processors are executed asynchronously and the plurality of processors share the memory.

Data processing system having plurality of processors and executing series of processings in prescribed order

The method and apparatus particularly adapted for reducing the storage capacity of line memories needed for temporarily storing image data for lines until image data for the last line is obtained in digital filtering. Inputted image data are divided into a plurality of blocks, each of which consists of image data obtained from n pixels. The integer n may assume a value of 8, 16, 32, etc. The constituents of one block after another are compressed such that image data consisting of 8 bits per pixel are converted into encoded data consisting of 2 bits per pixel. Data on a dynamic range and an average value for each block are added as a headder to the encoded data. Compressed image data are taken out of a buffer memory after being temporarily stored therein and, together with or separately from compressed image data newly outputted from a compression unit, subjected to image processing such as MTF correction in an arithmetic unit. Image processing to be carried out in the arithmetic unit normally includes expansion and correction to be carried out independently of or simultaneously with each other.

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Toyohashi, Japan

Mitsuru Obara