Ricoh Company, Ltd.

Jun Hosokawa

Kazuhiko Kobayashi

Tadashi Shinohara

Tetsuo Yamanaka

Nobuto Yokokawa

Toshiyuki Takahashi

Masato Yokoyama

Yuuji Matsuda

Yohhei Miura

Toshiyuki Andoh

Hiromichi Matsuda

Toshiyuki Ando

Kouta Fujimori

Motonori Hanada

Makoto Komatsu

Yuji Matsuda

Hiroyasu Shijo

Yohei Miura

Yasumori Nagahara

Kazuhiko Yuuki

Masata Yokoyama

Toshiyuki Yakahashi

An image forming apparatus including a plurality of detachable image forming devices each configured to form a color image, an image carrying device configured to carry the color images sequentially overlaid into a single color image, an exchange detecting device configured to detect an exchange operation of the plurality of detachable image forming devices, a test pattern reading device configured to read a predetermined test pattern formed by the plurality of detachable image forming devices on the image carrying device, and a controller configured to instruct the plurality of detachable image forming devices to form the predetermined test pattern on the image carrying device when the exchange detecting device detects the exchange operation, and to perform a color image position adjustment based on readings of the predetermined test pattern by the test pattern reading device.

Method and apparatus for image forming capable of effectively performing color image position adjustment

A method, apparatus, and program for driving a motor in a feedback control system, capable of suppressing oscillation of the motor are disclosed. A motor drive controller includes a drive motor, a detector, and a motor drive controller. The drive motor drives a moving body around a target moving speed. The detector detects a current moving speed of the moving body and output it as a detector pulse signal. The controller calculates a difference between the current moving speed and the target moving speed, calculates a control value based on the difference, calculates a pulse rate of a drive pulse signal based on the control value after having controlled the control value to be within a predetermined value, and feedback controls the drive motor based on the pulse rate.

Method, apparatus, and program for driving a motor in a feedback control system, capable of suppressing motor oscillation

A color image forming apparatus including a plurality of image forming devices, a transfer device including a transfer belt, a test pattern forming device configured to form, on the transfer belt, a test pattern including a plurality of marks formed by the image forming devices, an optical sensor configured to read the plurality of marks, and a checking device configured to determine whether reading by the optical sensor is performed correctly or not.

An image forming apparatus including an image carrying member, a transfer member, support rollers, a detecting mechanism, and a controller. The image carrying member supported by the support rollers, forms a toner image on its surface facing a surface of the transfer member, which transfers the toner image to a recording medium. The detecting mechanism includes a detection roller, a roller shaft, a moving member, and a sensor, and detects a speed of the image carrying member. The detection roller includes one support roller selected from the support rollers, and is provided with the roller shaft. The moving member is directly fixed to the roller shaft and rotates with the detection roller. The sensor detects a moving speed of the detection roller with the moving member. The controller controls a traveling speed of the image carrying member to a target speed based on a detection result of the sensor.

Method and apparatus for image forming capable of effectively reducing unevenness of density and color displacement of images

A color image forming apparatus including a plurality of image forming devices attachable to and detachable from a housing, a transfer device including a transfer belt, an exchange detecting device configured to detect exchange of the image forming devices, a test pattern forming device configured to form, on the transfer belt, a test pattern including a plurality of marks formed by the image forming devices, when the exchange detecting device detects an exchange of the image forming device, an optical sensor configured to read the plurality of marks, and a checking device configured to determine whether reading by the optical sensor is performed correctly or not.

An image forming apparatus including a plurality of detachable image forming devices each for forming a color image, an image carrying device for carrying the color images sequentially overlaid into a single color image, an exchange detecting device for detecting an exchange of the image forming devices, a test pattern reading device for reading a predetermined test pattern formed by the image forming devices on the image carrying device, and a controller configured to instruct the image forming devices to form the predetermined test pattern when either the detecting device detects the exchange, the fixing temperature is lower than a predetermined temperature, a color print adjustment command is provided, or the total number of color prints is greater than that at the last color print adjustment, and to perform color image position adjustment based on readings of the predetermined test pattern by the test pattern reading device.

A color image forming apparatus including a plurality of photosensitive drums on which toner images of different colors are respectively formed. An endless belt confronts the plurality of photosensitive drums. A drive source drives rotation of the endless belt, or alternatively plural drive sources drive the photosensitive drums to individually rotate. A memory stores pre-measured characteristics of a color misregistration of a color image in a sub-scanning direction of the apparatus, the color image formed by transferring images from respective of the plurality of photosensitive drums. Further, a control unit changes an average running speed of the endless belt, or alternatively an average running speed of at least some of the photosensitive drums, by controlling the drive sources, to compensate for color misregistration, based on the stored characteristics of color misregistration. The belt can either transport a paper sheet or have a color image formed thereon as an intermediate transfer device.

Apparatus and method for color image forming, and computer program product for driver controller

A method, apparatus, and program for driving a motor in a feedback control system, capable of suppressing oscillation of the motor rotational speed are disclosed. A motor drive controller includes a drive motor, a detector, and a motor drive controller. The drive motor drives a moving body around a target speed. The detector detects a current moving speed of the moving body and outputs it as a detector pulse signal. The controller calculates a difference between the current moving speed and the target moving speed, calculates a control value based on the difference, calculates a pulse rate of a drive pulse signal based on the control value after having controlled the control value to be within a predetermined value, and controls the drive motor based on the pulse rate.

An image forming apparatus including an image carrying member, a transfer member, support rollers, a detecting mechanism, and a controller. The image carrying member forms a toner image on its surface facing a surface of the transfer member, supported by the support rollers, which transfers the toner image to a recording medium. The detecting mechanism includes a detection roller, a roller shaft, a moving member, and a sensor, and detects a speed of the transfer member. The detection roller includes one support roller selected from the support rollers, and is provided with the roller shaft. The moving member is directly fixed to the roller shaft and rotates with the detection roller. The sensor detects a moving speed of the detection roller with the moving member. The controller controls a traveling speed of the transfer member to a target speed based on a detection result of the sensor.

A belt driving controller includes a driving roller having a radius ra plurality of driven rollers that is driven by rotation of the driving roller, the driven rollers having a radius ran endless belt that is wound on the driving roller and the driven rollers and an encoder that is attached to one of the driven rollers, and that outputs a signal. The rotation of the driving roller is controlled based on the signal from the encoder, and ()&#xd7;(r/r)&#x2266;1 is satisfied where &#x3b1;is a correction coefficient for a fluctuation in thickness of the endless belt caused by a belt winding angle on the driving roller, and &#x3b1;is a correction coefficient for a fluctuation in the thickness on the driven roller.

Belt driving controller, process cartridge, and image forming apparatus

A drive control method includes detecting an angular displacement of a rotor driven by a pulse motor, calculating a difference between the detected angular displacement and a preset target value of the angular displacement, and calculating a drive pulse frequency of a drive pulse signal used to drive the pulse motor. The pulse motor is driven by the drive pulse signal having the drive pulse frequency to allow the rotor at a constant angular velocity.

Apparatus for and method of driving motor to move object at a constant velocity

An image forming apparatus including a plurality of detachable image forming devices each for forming a color image, an image carrying device for carrying the color images sequentially overlaid into a single color image, an exchange detecting device for detecting an exchange of the plurality of detachable image forming devices, a test pattern reading device for reading a predetermined test pattern formed by the plurality of detachable image forming devices on the image carrying device, and a controller for instructing the plurality of detachable image forming devices to form the predetermined test pattern on the image carrying device when the exchange detecting device detects the exchange and perform a color image position adjustment based on readings of the predetermined test pattern by the test pattern reading device.

A full-color image forming apparatus forms a full-color image using a color-matching pattern of color components formed on an intermediate transfer belt. The image forming apparatus includes at least one pattern detection sensor that detects the color-matching pattern and generates pattern detection signals. A seam mark-detecting sensor detects a seam mark formed on the intermediate transfer belt and generates seam mark detection signals. The seam mark-detecting sensor is aligned with the pattern detection sensor on a same axis extending vertically relative to a traveling direction of the intermediate transfer belt. A memory stores digital signals converted from the pattern detection and seam mark detection signals. A seam mark detection signal deleting device deletes a prescribed seam mark detection signal from the pattern detection signals when the pattern detection signal and the prescribed seam mark detection signal occur simultaneously. A controlling device controls the image forming apparatus in accordance with the pattern detection and seam mark detection signals excluding the prescribed seam mark detection signal.

Belt type image forming apparatus and method that detects a color pattern

A method of color displacement detection for use in a color image forming apparatus sequentially forming image layers in different colors on a photosensitive member and overlaying the image layers on one after another into a color image on a transferring member. This method includes steps of forming, detecting, and calculating. The forming step forms a predetermined number of mark sets within one circumferential length surface of the transferring member. Each of the predetermined number of mark sets includes a predetermined number of different color marks arranged in a line in a moving direction of the transferring member. The detecting step detects the predetermined number of mark sets formed on the transfer member. The calculating step calculates mean values of displacement amounts of same color marks in different mark sets in the predetermined number of mark sets relative to respectively corresponding reference positions.

Method and apparatus for image forming capable of effectively performing color displacement detection

A method of image forming that employs detachable image forming mechanisms for forming color images, each individually using a color toner different from each other and an image carrying member for carrying the color images that are sequentially overlaid on one another into a single color image. A detecting step detects the exchange of one of the detachable image forming mechanisms. A further step performs an adjustment for eliminating displacements of color images formed by the detachable image forming mechanisms, in accordance with the detection of the exchange of one of the detachable image forming mechanisms detected in the detecting step.

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Tokyo, Japan

Jun Hosokawa