Patents by Inventor Takashi Hodoshima
Takashi Hodoshima has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Publication number: 20090207461Abstract: In an image forming apparatus, a distance adjusting unit adjusts an inter-unit distance between a contact unit and an image carrier by moving the image carrier or the contact unit by applying an opposing force to the image carrier or the contact unit against a biasing force applied by a biasing unit based on thickness information of a recording sheet acquired by a thickness-information acquiring unit and data indicating a relationship between the thickness information and an inter-unit distance change amount stored in a data storage unit.Type: ApplicationFiled: February 18, 2009Publication date: August 20, 2009Inventors: Takashi Hodoshima, Toshiyuki Andoh, Takashi Hashimoto, Hidetaka Noguchi, Seiji Hoshino, Tatsuhiko Oikawa, Tetsuo Watanabe
-
Publication number: 20090162118Abstract: A driving apparatus includes a driving unit, a driven unit driven by the driving unit, a driving control unit configured to control the driving unit by performing feed-forward control based on feed-forward target data determined in advance to reduce a speed change of the driven unit. The speed change of the driven unit is expressed substantially as a positive half cycle of a sinusoidal waveform having an amplitude and a time duration, and the feed-forward target data is calculated from the amplitude and the time duration to represent a rectangular waveform approximating the positive half cycle of the sinusoidal waveform.Type: ApplicationFiled: December 8, 2008Publication date: June 25, 2009Inventors: Hidetaka Noguchi, Toshiyuki Andoh, Takashi Hodoshima, Seiji Hoshino, Tatsuhiko Oikawa, Takashi Hashimoto
-
Publication number: 20090116860Abstract: An image forming device is disclosed that is able to enlarge a gap of a nipping portion with a simple and inexpensive structure, and able to reduce impact when a front end of a recording sheet runs into or a back end of the recording sheet passes through the nipping portion. The image forming device includes an image carrying unit, an image forming unit, a transfer unit, a conveyance unit, a determination unit that determines whether a thickness of the recording sheet is greater than a threshold value, and a cam member that rotates to enlarge or reduce the gap of the nipping portion between the image carrying unit and the transfer unit according to rotational positions of the cam member. When the thickness of the recording sheet is greater than the threshold, the cam member rotates so that the gap of the nipping portion is enlarged.Type: ApplicationFiled: August 25, 2008Publication date: May 7, 2009Inventors: Seiji Hoshino, Toshiyuki Andoh, Takashi Hodoshima, Takashi Hashimoto, Hidetaka Noguchi, Tatsuhiko Oikawa
-
Publication number: 20090060613Abstract: A load torque variation upon entry or exit of a sheet into a nipping portion is reduced while a nipping force necessary for image formation is provided. An image transfer apparatus, an image fixing apparatus, or a registration apparatus comprises an opposite roller, a transfer roller, and a compression spring for pressing the opposite roller onto the transfer roller. A sheet of transfer material is transported into a nipping portion between the opposite roller and the transfer roller, where an image on the opposite roller is transferred to the transfer material. The apparatus includes a retaining unit configured to retain a certain distance between the first rotating body and the second rotating body as long as the thickness of the transfer material that passes through the nipping portion remains the same.Type: ApplicationFiled: August 7, 2008Publication date: March 5, 2009Inventors: Hiromichi Matsuda, Toshiyuki Andoh, Takashi Hashimoto, Takashi Hodoshima, Tatsuhiko Oikawa, Hidetaka Noguchi, Seiji Hoshino, Makoto Komatsu
-
Publication number: 20080303202Abstract: A fluctuation detecting unit detects a fluctuation of an endless belt generated when a sheet is brought into contact with a predetermined position of the endless belt at an upstream side in a conveying direction from a nip portion based on fluctuation information acquired by a fluctuation information acquiring unit. An entry timing estimating unit estimates entry timing of the sheet into the nip portion based on a detection of the fluctuation. A correction control unit corrects a speed fluctuation of the endless belt generated when the sheet enters the nip portion by performing a feedforward control of a first driving unit based on the entry timing.Type: ApplicationFiled: May 28, 2008Publication date: December 11, 2008Inventors: Hidetaka NOGUCHI, Toshiyuki Andoh, Takashi Hodoshima, Tatsuhiko Oikawa, Seiji Hoshino, Hiromichi Matsuda, Makoto Komatsu, Takashi Hashimoto
-
Publication number: 20080232880Abstract: A sheet conveying device includes a pair of upstream rollers and a pair of downstream rollers each including a drive roller and a driven roller, a calculating unit, and a control unit. The upstream rollers include a measuring unit that obtains speed information of the upstream rollers. The calculating unit calculates a target value based on the speed information. The control unit controls the speed of the drive roller of the downstream rollers based on the target value.Type: ApplicationFiled: March 21, 2008Publication date: September 25, 2008Inventors: Hidetaka Noguchi, Toshiyuki Andoh, Seiji Hoshino, Takashi Hodoshima, Tatsuhiko Oikawa, Hiromichi Matsuda, Makoto Komatsu, Takashi Hashimoto
-
Publication number: 20080175612Abstract: A motor control device includes a pair of rotating members, a driving motor, and a timer-controller. The pair of rotating members nips and conveys a recording medium. The driving motor drives at least one rotating member of the pair of rotating members. The timer-controller calculates a time at which the recording medium passes through a nip formed by the pair of rotating members and controls the driving motor by correcting an excitation time of the driving motor near the time at which the recording medium passes through the nip formed by the pair of rotating members.Type: ApplicationFiled: January 11, 2008Publication date: July 24, 2008Inventors: Tatsuhiko Oikawa, Toshiyuki Andoh, Seiji Hoshino, Takashi Hodoshima, Hiromichi Matsuda, Makoto Komatsu, Takashi Hashimoto, Hidetaka Noguchi, Tetsuo Watanabe
-
Patent number: 6901233Abstract: An image forming apparatus of the present invention includes a bias power supply for applying a bias VB to a developer carrier on which a developer is deposited. A charge potential deposited on an image carrier, which faces the developer carrier for forming a latent image thereon, is 400 V or below in absolute value. Assume that the potential of the image carrier is lowered to VL after exposure, that a development potential is |VB?VL|, that the maximum set value of the development potential for development is |VB?VL|max, and that the development potential varies in a range satisfying relations: |VB?VL|?|VB?VL|max+|VB?VL|max×0.2 |VB?VL|?|VB?VL|max?|VB?VL|max×0.2 |VB?VL|max?300 V Then image density varies by a width of 10% of image density corresponding to the maximum set value of the development potential or less.Type: GrantFiled: December 11, 2003Date of Patent: May 31, 2005Assignee: Ricoh Company, Ltd.Inventors: Katsuhiro Aoki, Tsukuru Kai, Hajime Oyama, Osamu Ariizumi, Hisashi Shoji, Takashi Hodoshima, Yasuo Miyoshi
-
Patent number: 6856780Abstract: A developing method of the present invention uses a sleeve accommodating a stationary magnet roller formed with a plurality of magnetic poles and facing an image carrier. The sleeve is rotated to convey a developer, which is made up of toner grains and magnetic carrier grains and deposited on the sleeve, to a developing zone for thereby feeding the toner grains from a magnet brush formed by the developer to a latent image formed on the image carrier. When the developing zone is seen from the image carrier side, the ratio of the total area of voids present at the tips of the magnet brush to the total area of the developing zone is selected to be 25% or less.Type: GrantFiled: August 12, 2003Date of Patent: February 15, 2005Assignee: Ricoh Company, Ltd.Inventors: Ichiro Kadota, Takashi Hodoshima, Nobutaka Takeuchi, Teiichiro Takano
-
Publication number: 20040120733Abstract: An image forming apparatus of the present invention includes a bias power supply for applying a bias VB to a developer carrier on which a developer is deposited. A charge potential deposited on an image carrier, which faces the developer carrier for forming a latent image thereon, is 400 V or below in absolute value.Type: ApplicationFiled: December 11, 2003Publication date: June 24, 2004Inventors: Katsuhiro Aoki, Tsukuru Kai, Hajime Oyama, Osamu Ariizumi, Hisashi Shoji, Takashi Hodoshima, Yasuo Miyoshi
-
Publication number: 20040096244Abstract: A developing method of the present invention uses a sleeve accommodating a stationary magnet roller formed with a plurality of magnetic poles and facing an image carrier. The sleeve is rotated to convey a developer, which is made up of toner grains and magnetic carrier grains and deposited on the sleeve, to a developing zone for thereby feeding the toner grains from a magnet brush formed by the developer to a latent image formed on the image carrier. When the developing zone is seen from the image carrier side, the ratio of the total area of voids present at the tips of the magnet brush to the total area of the developing zone is selected to be 25% or less.Type: ApplicationFiled: August 12, 2003Publication date: May 20, 2004Inventors: Ichiro Kadota, Takashi Hodoshima, Nobutaka Takeuchi, Teiichiro Takano
-
Patent number: 6721516Abstract: An image forming apparatus of the present invention includes a bias power supply for applying a bias VB to a developer carrier on which a developer is deposited. A charge potential deposited on an image carrier, which faces the developer carrier for forming a latent image thereon, is 400 V or below in absolute value. Assume that the potential of the image carrier is lowered to VL after exposure, that a development potential is |VB−VL|, that the maximum set value of the development potential for development is |VB−VL|max, and that the development potential varies in a range satisfying relations: |VB−VL|≦|VB−VL|max+|VB−VL|max×0.2 |VB−VL|≧|VB−VL|max−|VB−VL|max×0.Type: GrantFiled: January 22, 2002Date of Patent: April 13, 2004Assignee: Ricoh Company, Ltd.Inventors: Katsuhiro Aoki, Tsukuru Kai, Hajime Oyama, Osamu Ariizumi, Hisashi Shoji, Takashi Hodoshima, Yasuo Miyoshi
-
Patent number: 6658227Abstract: The development is performed under a condition that |Q2|−|Q1|/|Q1≦±0.45. Here, Q1 denotes an average amount of charge on toner held on a development roller and carried toward a development region immediately before development. Q2 denotes an average amount of charge on toner immediately before development held and carried toward the development region in the state immediately after development of an electrostatic latent image on a development drum. This is effective to allow the amount of charge q/m on toner held on the development roller to have a variation rate of 45% or below and an afterimage rate R within 2%.Type: GrantFiled: July 5, 2002Date of Patent: December 2, 2003Assignee: Ricoh Company, LimitedInventors: Hajime Oyama, Tsukuru Kai, Katsuhiro Aoki, Takashi Hodoshima, Yasuo Miyoshi, Ichiro Kadota
-
Patent number: 6608984Abstract: An image forming apparatus of the type which develops a latent image on an image carrier with toner stored in a developing unit and transferring the resulting toner image to a recording medium. The developing unit includes a developer carrier which contacts the image carrier at least at two spaced apart points with a gap being formed between the at least two points of contact. A moving mechanism will move opposite ends of the developer carrier independent distances relative to one another so as to eliminate the gap and establish full contact between the image carrier surface and developer carrier surface.Type: GrantFiled: April 24, 2000Date of Patent: August 19, 2003Assignee: Ricoh Company, Ltd.Inventors: Junichi Matsumoto, Katsuhiro Aoki, Takashi Hodoshima
-
Patent number: 6526248Abstract: A developing device for an image forming apparatus of the type feeding a one-ingredient or two-ingredient type developer, forming a thin toner layer on a developing roller or toner support member and developing a latent image with the toner layer is disclosed. The toner support member has a surface that is chargeable to the same polarity as toner. The toner support member therefore serves to simply support the toner without electrostatically effecting the toner, so that the development of a latent image is free from the influence of the static electricity of the toner support member. This successfully enhances image quality. A photoconductive element has a coefficient of friction &mgr; confined in the range of 0.1<&mgr;<0.4, preventing the toner from depositing on and contaminating the background area of the element. In addition, the surface of the photoconductive element is protected and has its service life extended.Type: GrantFiled: September 15, 2000Date of Patent: February 25, 2003Assignee: Ricoh Company, Ltd.Inventors: Katsuhiro Aoki, Takashi Hodoshima, Hajime Oyama
-
Publication number: 20030035663Abstract: The development is performed under a condition that |Q2|−|Q1|/|Q1≦±0.45. Here, Q1 denotes an average amount of charge on toner held on a development roller and carried toward a development region immediately before development. Q2 denotes an average amount of charge on toner immediately before development held and carried toward the development region in the state immediately after development of an electrostatic latent image on a development drum. This is effective to allow the amount of charge q/m on toner held on the development roller to have a variation rate of 45% or below and an afterimage rate R within 2%.Type: ApplicationFiled: July 5, 2002Publication date: February 20, 2003Inventors: Hajime Oyama, Tsukuru Kai, Katsuhiro Aoki, Takashi Hodoshima, Yasuo Miyoshi, Ichiro Kadota
-
Patent number: 6505014Abstract: An image forming apparatus of the present invention includes an image carrier made up of a conductive base and photoconductive layer and a toner carrier to which a bias for development is applied. The toner carrier conveys toner deposited thereon to a developing position where the toner carrier faces the image carrier, thereby developing a latent image formed on the image carrier. The apparatus effects low-voltage development that protects the image carrier from electrostatic fatigue, obviates background contamination, and realizes image density as high as 0.5 ×10−3 g/cm2 or above in terms of the amount of toner deposition. Further, the apparatus implements faithful development of the latent image by reducing the edge effect. An image forming process unit removable from the apparatus is also disclosed.Type: GrantFiled: September 28, 2001Date of Patent: January 7, 2003Assignee: Ricoh Company, Ltd.Inventors: Katsuhiro Aoki, Hisashi Shoji, Tsukuru Kai, Hajime Oyama, Noriyoshi Tarumi, Takashi Hodoshima, Yasuo Miyoshi
-
Publication number: 20020154917Abstract: An image forming apparatus of the present invention includes a bias power supply for applying a bias VB to a developer carrier on which a developer is deposited. A charge potential deposited on an image carrier, which faces the developer carrier for forming a latent image thereon, is 400 V or below in absolute value.Type: ApplicationFiled: January 22, 2002Publication date: October 24, 2002Inventors: Katsuhiro Aoki, Tsukuru Kai, Hajime Oyama, Osamu Ariizumi, Hisashi Shoji, Takashi Hodoshima, Yasuo Miyoshi
-
Patent number: 6463244Abstract: A developing device for an image forming apparatus includes a developing roller for conveying toner deposited thereon to a developing region where it faces a photoconductive element. A magnet brush roller conveys a two-ingredient type developer, which consists of toner and magnetic particles, deposited thereto to a toner supplying region where it faces the developing roller. In the toner supplying region, only the toner is supplied from the magnet brush roller to the developing roller. The distribution of the number of toner particles for an amount of charge differs from the developing roller to the magnet brush roller.Type: GrantFiled: March 23, 2001Date of Patent: October 8, 2002Assignee: Ricoh Company, Ltd.Inventors: Katsuhiro Aoki, Hajime Oyama, Takashi Hodoshima
-
Publication number: 20020039496Abstract: An image forming apparatus of the present invention includes an image carrier made up of a conductive base and a photoconductive layer and a toner carrier to which a bias for development is applied. The toner carrier conveys toner deposited thereon to a developing position where the toner carrier faces the image carrier, thereby developing a latent image formed on the image carrier. The apparatus effects low-voltage development that protects the image carrier from electrostatic fatigue, obviates background contamination, and realizes image density as high as 0.5×10−3 g/cm2 or above in terms of the amount of toner deposition. Further, the apparatus implements faithful development of the latent image by reducing the edge effect. An image forming process unit removable from the apparatus is also disclosed.Type: ApplicationFiled: September 28, 2001Publication date: April 4, 2002Inventors: Katsuhiro Aoki, Hisashi Shoji, Tsukuru Kai, Hajime Oyama, Noriyoshi Tarumi, Takashi Hodoshima, Yasuo Miyoshi