Ricoh Company, Ltd.

Kabushiki Kaisha Toshiba

Masato Yokoyama

Kazuhiko Kobayashi

Nobuto Yokokawa

Masumi Sato

Toshiyuki Andoh

Hiromichi Matsuda

Tadashi Shinohara

Toshiyuki Takahashi

Jun Hosokawa

Yuuji Matsuda

Yohhei Miura

Motokazu Yasui

Hiroshi Okamura

Yuji Matsuda

Yohei Miura

Ryoji Imai

Masanori Horike

Toshiyuki Uchida

Takaya Muraishi

Hiroshi Yoshizawa

Tsumori Sato

Toshiyuki Ando

Katsumi Masuda

Makoto Komatsu

Sadao Takahashi

Koji Suzuki

Masaru Tanaka

Keiichi Serizawa

Tetsuya Kimura

Keiji Okamoto

Yasumori Nagahara

Yasumasa Tomita

Hiroyuki Ohkaji

Toshiaki Aoyagi

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

An ink jet recording apparatus performs a print operation by controlling an ink jet recording head to eject ink drops there from against front and back surfaces of a recording sheet at a print position. The apparatus includes a transporting mechanism for transporting a portion of the recording sheet to a location outside of the apparatus after a completion of the print operation on the front surface of the recording sheet and just before printing of the back surface of the recording sheet.

Ink jet recording apparatus capable of performing a duplex print operation

A scanning lens for an optical scanner includes a specific adjusting axis and a curved surface. The specific adjusting axis makes a rotating center of the scanning lens and center of the curved surface. The scanning lens is disposed on a holding member having a receiving surface, so that the curved surface is in contact with the receiving surface. A position of the scanning lens is adjusted by a rotating mechanism that rotates the scanning lens.

Scanning lens for optical scanner, optical scanner, and image forming apparatus

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

An image forming apparatus includes a belt stretched across rollers and a resist rotary member that feeds out a recording medium on the belt. A correlation between a velocity of the belt and the resist rotary member is obtained. A target velocity of the belt or the resist rotary member, at which a difference between the velocity when the recording medium is in contact with both the belt and the resist rotary member and the velocity when the recording medium is not in contact with at least either the belt or the resist rotary member is minimum, is determined based on the correlation.

Image forming apparatus having a resist rotary member

A belt driving control apparatus, the belt driving control apparatus having an endless belt, a driving roller driving the endless belt, a driving motor driving the driving roller, at least one idler roller being dependent on the endless belt, and an encoder attached to one idler roller. The belt driving control apparatus includes a structure where a control target value of the driving motor is set so that an effective speed of the endless belt is constant and the driving motor is drive-controlled so that the control target value is satisfied.

Belt driving control apparatus and image forming apparatus which uses a moving average process and a revolution average process

A mark detecting unit detects a mark that is a reference position of an endless belt. An angular-displacement-error detecting unit detects an angular displacement error of an encoder caused by thickness fluctuation of the endless belt. A first calculating unit calculates a phase and a maximum amplitude to the mark. A second calculating unit calculates correction data according to a distance from the mark on the endless belt. A belt-drive control device controls a belt driving unit by adding the correction data to a preset control target value to stabilize speed fluctuation of the endless belt due to the thickness fluctuation.

Belt-drive control device, color-shift detecting method, color-shift detecting device, and image forming apparatus

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 includes an image bearing member having a photosensitive surface and an optical writing apparatus generating a laser beam modulated according to image data. The optical writing apparatus includes a housing, an optical deflector, an f-theta lens and a separator. The optical deflector is configured to rotate to deflect the laser beam. The f-theta lens is configured to correct the laser beam deflected by the optical deflector and to transmit a corrected laser beam towards the image bearing member. The separator is configured to separate an inside space of the housing into at least two sections including a first section in which the optical deflector is mounted and a second section in which the f-theta lens is mounted. The separator includes a heat resistant transparent plate disposed at a position of crossing passage of the laser beam between the optical deflector and the f-theta lens.

Method and apparatus for image forming capable of preventing image quality deterioration induced by heat from an optical deflector

A passbook printing apparatus comprises a movable tension roller correcting slack of an intermediate transfer film resulting from a different in a feed speed between a film drive roller and a film wind-up reel, and a control device operating the film wind-up reel to apply a predetermined tension to the intermediate transfer material in a state of stopping the film drive roller, thereby moving and fixing the tension roller to a predetermined position, and thereafter, feeding the intermediate transfer film by a predetermined distance by the film drive roller to position it to the transfer position.

Printing apparatus and method for passbooks

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.

To compensate for the variation in the output signal from an encoder due to the variation in the thickness of an endless belt, an apparatus includes: a detector that detects a reference position on the endless belt; a correction-value calculating unit that calculates a correction value for each position on the endless belt based on the thickness; and a target-value calculating unit that adjusts a target value for controlling a driving motor based on the correction value corresponding to a distance from the reference position to the current position.

Apparatus for controlling driving of endless belt, and image forming apparatus

An optical scanner includes a light source which emits a light beam, a reflection mirror which has a reflection surface, a first axis parallel to a main-scanning direction, and a second axis along the reflection surface and perpendicular to the first axis, and an optical element which adjusts a position of a scanning line in a sub-scanning direction, the optical element having a beam-incidence surface, a third axis parallel to the main-scanning direction on the beam-incidence surface, and a fourth axis perpendicular to the third axis and along a beam-incidence direction. A first adjustment unit is provided to rotate the reflection mirror around the second axis in order to attain uniformity of a scanning speed. A second adjustment unit is provided to rotate the optical element around the fourth axis in order to correct an inclination of the scanning line to a desired position of the scanning line.

Optical scanner, optical-path adjustment method, and image forming apparatus

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.

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Kanagawa, Japan

Masato Yokoyama