Fujitsu Corporation

Fuji Xerox Co., Ltd.

Fuji Photo Film Company, Limited

Hiroshi Nou

Mitsuhiro Mori

Akira Iwaishi

Masatoshi Kimura

Kunihiko Sato

Masahiro Wanou

Kouichi Sanpei

Sachio Sasaki

Hideki Kamaji

Masae Ikeda

Ryo Kitao

Satoshi Semba

Kazunori Hirose

Yukio Nishio

Masao Konishi

Tomohisa Mikami

Shigenobu Utaka

Teruki Kishimoto

Toshio Tooda

Shigeyoshi Nakamura

Teturou Nakashima

Shino Sakai

Akiyoshi Iwamasa

Akihiko Ishii

Hideaki Iwasaki

Masashi Ogasawara

Nobuo Suematsu

An image forming apparatus that includes an image forming component, a flash fixing component and a control component is provided. The image forming component forms toner images using at least two toners respectively having different colors and transfers the formed toner images onto a recording medium. The flash fixing component emits a flash light onto the recording medium onto which the toner images have been transferred by the image forming component and fixes the toner images. The control component that controls the image forming component to form the toner images so that, among the toner images, a second color toner is adhered to a surface of a toner layer formed by a first toner color at a region at which the toner layer formed by the first toner color is formed, the absorbance of the second color toner being lower than that of the first color toner.

Image forming apparatus, image forming control method, and recording medium recording image forming control program

The fixing apparatus used in an image forming apparatus and fixing an image on a recording medium, the fixing apparatus is provided with: a flash lamp that emits flash light for fixing the image; and a reflection member that has a reflection surface reflecting the flash light emitted from the flash lamp to the recording medium. A shape of the reflection surface is configured so as to be deformable.

Reflection member for a fixing unit of an, image forming apparatus and a fixing method using the reflection member

A flash fixing device comprises a first and second flash lamps that emit flashes of light that fix a toner image transferred onto a recording medium and a light emission control unit that controls the light emissions of the first and second flash lamps so that the light flashes emitted from the first flash lamp and the second flash lamp are each irradiated at different timing on each portion on the recording medium.

Flash fixing device, image forming device using the same, and flash lamp light emission control method

A flash fixing device is disclosed. The flash fixing device has a group of main flash lamps which emit main flash light for fixing a toner image on a recording medium; an auxiliary flash lamp provided at a position corresponding to between a pair of flash lamps of the group of main flash lamps; and a light-emission control unit controlling light-emission of the group of main flash lamps and light-emission of the auxiliary flash lamp by using a predetermined relationship. Also disclosed is an image forming device having the flash fixing device.

Flash fixing device and image forming device

A fixing device that applies heat energy to a recording medium having a toner image formed thereon to fix the toner image includes a flash fixing part that includes a flash lamp disposed in non-contact with the recording medium and applies heat energy to the toner image formed on the recording medium through discharge luminescence of a gas in the flash lamp, and an air stream spraying part that is disposed in non-contact with the recording medium on a downstream side of the flash fixing part in a transporting direction of the recording medium and sprays an air stream at a prescribed temperature onto a surface of the recording medium.

Fixing device and image forming apparatus using the same

A smoothing method extracts an evaluation window including a target pixel of a multi-value image data in which tone is represented by a multi-value in units of pixels, and judges black and white of the target pixel according to a predetermined rule, and binarizes pixel data within the evaluation window. Further, the smoothing method generates a correction value based on collating binarized pixel data within the evaluation window and a look-up table which stores patterns in vicinities of the target pixel, and outputs a multi-value correction signal in which the correction value is converted into a multi-value.

Smoothing method, smoothing circuit and image output apparatus

In an inkjet head, both tones and smoothing can be represented suitably through use of a small number of drive waveforms. A drive waveform generator unit () generates drive waveforms for emitting a ink particle to form dots of a same size within one cycle that is an integral fraction of the cycle for one pixel, a print data generator unit () generates print data of a plurality of bits for selecting said drive waveform in said cycle for one pixel, and a head drive unit () drives the nozzles of said head by selecting said drive waveform in accordance with said print data. Thereby, tones and smoothing can be represented suitably, through use of a small number of different waveforms.

On-demand inkjet printer and drive method and drive circuit for same

An ink jet printer comprises a color head having a plurality of nozzles arranged on a head carrier, each of the plurality of nozzles injecting color ink particles by the drive of a piezoelectric element; and a monochrome head having a plurality of nozzles arranged the head carrier, each of the plurality of nozzles injecting monochrome ink particles by the drive of a piezoelectric element. Within a single scanning of the head carrier, a control unit switches the printing mode between a color printing mode by the color head and a monochrome printing mode by the monochrome head, to thereby provide a control of printing. For the color-printing mode, a multivalued intensity mode is set, and for the monochrome-printing mode, a high-resolution mode is set, where the resolution of the monochrome head is integer times the resolution of the color head.

Ink jet printer

It is an exemplified object of the present invention is to provide an inkjet printer having a head drive circuit that can generate a less distorted drive waveform stably using a smaller-size and smaller-capacitance transistor than the conventional. An inkjet head of the present invention comprises a head which includes a plurality of piezoelectric elements and may jet ink using the piezoelectric elements, a carriage which has the head and moves with the head, and a one-chip head drive circuit, provided in the carriage, which receives a control signal and a drive signal for driving the piezoelectric elements, and drives the head, wherein the head drive circuit includes a plurality of selection parts, connected to each of the piezoelectric elements, which may receive the drive signal, a control part, coupled to the selection parts, which controls the selection parts based on the control signal, and selects a piezoelectric element to be driven from among the piezoelectric elements, and a plurality of current amplifier parts, provided in every selection part and piezoelectric element, which amplify the drive signal to be supplied to the piezoelectric element to be driven. The current amplifier part in the head drive circuit is provided for each piezoelectric element without requiring a large-size transistor seen in the prior art.

Head drive circuit and inkjet printer having the same

In an inkjet printing device, at least two kinds of drive waveforms are selectively fed to each of plezoelectric elements for controlling an injection amount of ink to be jetted toward a print medium via a corresponding nozzle. One of the drive waveforms is in the form of a cardiac waveform which has two voltage changing points in one drive period thereof. At the voltage changing point, a sign of slope of voltage variation is inverted. In the cardiac waveform, a voltage at one of the voltage changing points is set lower than a standby voltage, while a voltage at the other voltage changing point is set higher than the standby voltage.

Inkjet printing device and method

Disclosed is a method of driving a piezo-electric type ink jet head for jetting inks out of a nozzle by making use of a distortion of a piezo-electric element. The driving method includes a first step of driving the piezo-electric element so that a meniscus of inks is receded from an initial position of the nozzle to a first position within the nozzle, a second step of driving the piezo-electric element so that the meniscus quickly advances from the first position to a second position within the nozzle, and a third step of driving the piezo-electric element so that the meniscus slowly advances from the second position to the initial position. A particle quantity of ink particles is changed by changing a movement quantity from the first position to the second position in the second step.

Method of driving piezo-electric type ink jet head

An electrophotographic recording apparatus includes a photosensitive drum on which an electrostatic latent image can be written, a developing device for developing the latent image of a charged visible image with a one-component developer, and a transferring device for electrostatically transferring the charged visible image from the drum to a sheet or paper. The developing device has a conductive foam rubber roller for entraining the developer to form a developer layer therearound and for bringing the layer to the drum for the development of the latent image, a conductive blade resiliently engaged with the foam rubber roller for uniformly regulating a thickness of the developer, and an electric source for applying electric energy to the blade to electrically charge the developer layer by a charge-injection effect. The transferring device has a conductive foam rubber transfer roller in contact with the drum, and an electric source for applying energy to the transfer roller to give a paper an electric charge having a polarity opposite to that of the charged visible image during a passage of a recording medium through a nip between the drum and the transfer roller.

Electrophotographic recording apparatus using developing device with one-component type developer and having combination of charge injection effect and conductive contact type charger

An image forming apparatus capable of preventing unnecessary adhesion of a developer to an uncharged region of a latent image carrier. The image forming apparatus includes an endless latent image carrier, a charging unit for charging the latent image carrier, a latent image forming unit for forming a latent image on the latent image carrier charged, a developing unit for developing the latent image formed on the latent image carrier with a developer by supplying the developer to the latent image carrier under application of a developing bias voltage, and a transfer unit for transferring the image developed on the latent image carrier to a sheet. The image forming apparatus further includes a driving member for rotating the latent image carrier and for driving the developing unit to supply the developer to the latent image carrier, and a controller for effecting sequence control such that the application of the developing bias voltage to the developing unit is started a predetermined time after the rotation of the latent image carrier and the drive of the developing unit and also the charging operation of the charging unit have been started. Alternatively, a driving member for driving the developing unit is provided separately, and the controller effects sequence control such that the drive of the developing unit and the application of the developing bias voltage to the developing unit are started a predetermined time after the rotation of the latent image carrier and the charging operation of the charging unit have been started.

Image forming apparatus capable of preventing adhesion of a developer to

A toner image transferring device has a roller formed of a conductive rubber foam material having a resistivity of more than 10.sup.7 .OMEGA.cm. In a toner image transferring process, a constant current is applied to the roller, whereby a charged toner image can be transferred to a sheet or paper at a desired toner transfer efficiency regardless of a size of the paper or sheet. To remove a toner pollution of the roller, a constant voltage having a polarity opposite to that of the charged toner is applied to the roller. The roller is constituted such that pore openings appear over a surface of the roller, whereby a residual part of a toner polluting the roller will not leave a stain on a rear surface of the sheet or paper.

Conductive roller transfer device with improved transfer efficiency and

A toner image transferring device is applied to, for example, an electrophotographic printer for electrostatically transferring a charged toner image from a photosensitive drum to a sheet or paper. The device encompasses a transfer charger disposed near the drum to form a clearance therebetween for feeding an electric charge to the sheet or paper through which the sheet or paper is passed, an electric source for supplying an electric energy to the transfer charger to give the sheet or paper an electric charge having a polarity opposite to that of the charge of the toner image, and a controller for controlling the electric energy output from the electric source the transfer charger so that a leading edge of the sheet or paper can be prevented from being excessively charged.

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Kawasaki, Japan

Hiroshi Nou