Patents by Inventor Eisaku Murakami

Eisaku Murakami 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: 20070154246
    Abstract: A cleaning device, a process cartridge, an image forming apparatus and toner are disclosed to maintain improved cleaning performance for a long time. The cleaning device includes a cleaning blade, an antifriction agent coating part and a toner removing part. The cleaning blade is disposed in contact with a surface of an image support body. The antifriction agent coating part coats a solid antifriction agent on the surface of the image support body, and is disposed in an upstream side from the cleaning blade with respect to a rotational direction of the image support body. The toner removing part removes toner particles, and is disposed in an upstream side from the antifriction agent coating part with respect to the rotational direction of the image support body.
    Type: Application
    Filed: March 13, 2007
    Publication date: July 5, 2007
    Inventors: Takeshi Shintani, Takuji Yoneda, Toshio Koike, Masato Yanagida, Naohiro Kumagai, Hiroyuki Nagashima, Atsushi Sampe, Eisaku Murakami, Masanori Kawasumi, Takeshi Uchitani, Masami Tomita
  • Patent number: 7228099
    Abstract: A cleaning device, a process cartridge, an image forming apparatus and toner are disclosed to maintain improved cleaning performance for a long time. The cleaning device includes a cleaning blade, an antifriction agent coating part and a toner removing part. The cleaning blade is disposed in contact with a surface of an image support body. The antifriction agent coating part coats a solid antifriction agent on the surface of the image support body, and is disposed in an upstream side from the cleaning blade with respect to a rotational direction of the image support body. The toner removing part removes toner particles, and is disposed in an upstream side from the antifriction agent coating part with respect to the rotational direction of the image support body.
    Type: Grant
    Filed: May 3, 2004
    Date of Patent: June 5, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Takeshi Shintani, Takuji Yoneda, Toshio Koike, Masato Yanagida, Naohiro Kumagai, Hiroyuki Nagashima, Atsuhsi Sampe, Eisaku Murakami, Masanori Kawasumi, Takeshi Uchitani, Masami Tomita
  • Patent number: 7218877
    Abstract: A charging device including a charging roller having a metal cylinder and an elastic layer located thereon, and a cleaner for cleaning the surface of the charging roller. The cleaner includes a driving shaft and a cleaning roller which is rotatably mounted on the driving shaft. The cleaning roller is made of a non-cellular foam resin having a density of from 5 to 15 kg/m3 and a tensile strength of from 1.2 to 2.2 kg/cm2.
    Type: Grant
    Filed: March 30, 2006
    Date of Patent: May 15, 2007
    Assignee: Ricoh Company Limited
    Inventors: Masato Yanagida, Hiroyuki Nagashima, Naohiro Kumagai, Toshio Koike, Atsushi Sampe, Masanori Kawasumi, Eisaku Murakami, Takeshi Uchitani, Masami Tomita, Takeshi Shintani, Tsutomu Yamakami
  • Publication number: 20070065178
    Abstract: A conductive member forming a charging roller having high durability which maintains a stable gap with respect to an abutting member, comprising a long conductive supporting body, an electrical resistance adjusting layer, and gap maintaining members, wherein, taking X2 to be the thickness of the portions of the gap maintaining members which oppose the end faces of the electrical resistance adjusting layer, the relationship 1 mm?X2?3 mm is satisfied, taking X3 to be the interval between the end faces of the electrical resistance adjusting layer and the gap maintaining members which oppose these end faces, the relationship 0.
    Type: Application
    Filed: September 8, 2006
    Publication date: March 22, 2007
    Inventors: Eiji Shimojo, Masanori Kawasumi, Yoshiyuki Kimura, Masahiko Satoh, Takeshi Uchitani, Hideki Zemba, Yutaka Narita, Shunichi Hashimoto, Eisaku Murakami, Shin Kayahara
  • Patent number: 7184684
    Abstract: An image forming apparatus includes a frame body, a frame cover supported by the frame body so as to be capable of opening and closing, an image forming unit that forms a toner image on an image carrier, a cleaning unit that removes and collects residual toner from the image carrier, and a toner container for accumulating the toner collected by the cleaning unit. The toner container is supported by the frame cover.
    Type: Grant
    Filed: September 27, 2005
    Date of Patent: February 27, 2007
    Assignee: Ricoh Company, Limited
    Inventors: Eisaku Murakami, Hideo Yoshizawa, Hiroyuki Nagashima, Yoshiyuki Kimura, Hideki Zemba, Eiji Kurimoto, Hiroshi Ishii, Yuji Arai
  • Publication number: 20070036595
    Abstract: A cleaning unit includes a cleaning blade that cleans toner on an image carrier and a brush-shaped roller that applies a lubricant of a molded lubricant on the image carrier. The brush-shaped roller is insulative, and delivers the toner cleaned by the cleaning blade to inside of the cleaning unit.
    Type: Application
    Filed: October 25, 2006
    Publication date: February 15, 2007
    Inventors: Ken Amemiya, Masato Yanagida, Naohiro Kumagai, Takeshi Shintani, Takaaki Tawada, Yuji Arai, Toshio Koike, Takuji Yoneda, Takeshi Tabuchi, Yutaka Takahashi, Eisaku Murakami, Takeshi Uchitani, Masami Tomita, Masanori Kawasumi
  • Publication number: 20070014588
    Abstract: A charging device including: a charging roller having a metal cylinder and an elastic layer located on the metal cylinder; a cleaner configured to clean the charging roller, which includes an electroconductive brush roller including a roller having a shaft; and hair located overlying the roller, wherein the hair includes a fiber which has a width of from 0.1 to 20 denier, and a length of from 0.3 to 2.5 mm and which is planted at a density of from 7,000 to 46,000 lines/cm2, and a member configured to impart substantially the same potential as that of the charging roller to the electroconductive brush roller when a bias voltage is applied to the charging roller. A process cartridge and an image forming apparatus including the charging device are also provided.
    Type: Application
    Filed: June 30, 2006
    Publication date: January 18, 2007
    Inventors: Masato Yanagida, Hiroyuki Nagashima, Naohiro Kumagai, Toshio Koike, Atsushi Sampe, Masanori Kawasumi, Eisaku Murakami, Takeshi Uchitani, Tokuya Ohjimi, Masami Tomita, Takeshi Shintani
  • Patent number: 7149465
    Abstract: A cleaning unit includes a cleaning blade that cleans toner on an image carrier and a brush-shaped roller that applies a lubricant of a molded lubricant on the image carrier. The brush-shaped roller is insulative, and delivers the toner cleaned by the cleaning blade to inside of the cleaning unit.
    Type: Grant
    Filed: August 20, 2004
    Date of Patent: December 12, 2006
    Assignee: Ricoh Company, Limited
    Inventors: Ken Amemiya, Masato Yanagida, Naohiro Kumagai, Takeshi Shintani, Takaaki Tawada, Yuji Arai, Toshio Koike, Takuji Yoneda, Takeshi Tabuchi, Yutaka Takahashi, Eisaku Murakami, Takeshi Uchitani, Masami Tomita, Masanori Kawasumi
  • Patent number: 7139504
    Abstract: A charging device including: a charging roller having a metal cylinder and an elastic layer located on the metal cylinder; a cleaner configured to clean the charging roller, which includes an electroconductive brush roller including a roller having a shaft; and hair located overlying the roller, wherein the hair includes a fiber which has a width of from 0.1 to 20 denier, and a length of from 0.3 to 2.5 mm and which is planted at a density of from 7,000 to 46,000 lines/cm2, and a member configured to impart substantially the same potential as that of the charging roller to the electroconductive brush roller when a bias voltage is applied to the charging roller. A process cartridge and an image forming apparatus including the charging device are also provided.
    Type: Grant
    Filed: February 11, 2004
    Date of Patent: November 21, 2006
    Assignee: Ricoh Company Limited
    Inventors: Masato Yanagida, Hiroyuki Nagashima, Naohiro Kumagai, Toshio Koike, Atsushi Sampe, Masanori Kawasumi, Eisaku Murakami, Takeshi Uchitani, Tokuya Ohjimi, Masami Tomita, Takeshi Shintani
  • Publication number: 20060251438
    Abstract: A method and an apparatus of controlling a charge voltage including the steps of applying, charging, detecting, and determining. The applying step applies an application voltage having a direct-current voltage and an alternating-current voltage superimposed onto the direct-current voltage to a charge-applying member to charge a charge carrier. The changing step charges the alternating-current voltage of the application voltage. The detecting step detects an alternating current flowing through the charge carrier when the charge-applying member applies the application voltage to the charge carrier. The determining step determines a value of the alternating-current voltage of the application voltage based on at least two alternating currents detected by the alternating-current detector.
    Type: Application
    Filed: May 9, 2006
    Publication date: November 9, 2006
    Inventors: Takeshi Uchitani, Eisaku Murakami, Yoshiyuki Kimura, Masahiko Satoh, Masanori Kawasumi, Hideki Zemba, Eiji Shimojo, Shunichi Hashimoto, Shin Kayahara
  • Patent number: 7130564
    Abstract: An image forming apparatus includes an image bearing member configured to form an electrostatic latent image on a surface thereof, and a separating mechanism configured to separate an irregular charge toner from a residual toner remaining on the surface of the image bearing member after a completion of an image forming process, to provide an extra travel passage to give a time delay to the irregular charge toner, and to return the irregular charge toner with the time delay to the surface of the image bearing member.
    Type: Grant
    Filed: June 24, 2004
    Date of Patent: October 31, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Eisaku Murakami, Toshio Koike, Masato Yanagida, Naohiro Kumagai, Takeshi Shintani, Masanori Kawasumi, Atsushi Sampe, Masami Tomita, Hiroyuki Nagashima, Takeshi Uchitani
  • Publication number: 20060216085
    Abstract: A cleaning unit includes a first blade and a second blade. The first blade is in contact with an image carrier or a paper carrier and removes adhered substances remained on surface of these. The second blade has an abrasive layer that is formed by including abrasive particles in an elastic material and is disposed in the downstream side of the first blade. The second blade is allowed to be in contact with the image carrier 1 or the paper carrier. Volume occupancy of abrasive particles in an area of contact of the second blade with either the image carrier or the paper carrier is not less than 50 percent and not more than 90 percent.
    Type: Application
    Filed: May 26, 2006
    Publication date: September 28, 2006
    Inventors: Eisaku Murakami, Masami Tomita, Masanori Kawasumi, Toshio Koike, Naohiro Kumagai, Atsushi Sampe, Takeshi Shintani, Masato Yanagida, Yutaka Takahashi, Hiroya Hirose, Shin Hasegawa, Hiroyuki Nagashima, Takeshi Uchitani, Kazunori Karasawa, Kentaroh Matsumoto, Tokuya Ohjimi, Mugijiroh Uno
  • Patent number: 7110696
    Abstract: A cleaning unit includes a first blade and a second blade. The first blade is in contact with an image carrier or a paper carrier and removes adhered substances remained on surface of these. The second blade has an abrasive layer that is formed by including abrasive particles in an elastic material and is disposed in the downstream side of the first blade. The second blade is allowed to be in contact with the image carrier 1 or the paper carrier. Volume occupancy of abrasive particles in an area of contact of the second blade with either the image carrier or the paper carrier is not less than 50 percent and not more than 90 percent.
    Type: Grant
    Filed: September 24, 2003
    Date of Patent: September 19, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Eisaku Murakami, Masami Tomita, Masanori Kawasumi, Toshio Koike, Naohiro Kumagai, Atsushi Sampe, Takeshi Shintani, Masato Yanagida, Yutaka Takahashi, Hiroya Hirose, Shin Hasegawa, Hiroyuki Nagashima, Takeshi Uchitani, Kazunori Karasawa, Kentaroh Matsumoto, Tokuya Ohjimi, Mugijiroh Uno
  • Patent number: 7110699
    Abstract: An image forming apparatus of the present invention includes a sheet affixed at one edge portion and including a flat surface in the other edge portion. The flat surface is formed with a plurality of grooves each extending over the image forming range of a photoconductive drum perpendicularly to the direction in which the surface of the drum moves. The sheet is deformed such that the flat portion contacts the surface of the drum. In this condition, the downstream edges of the grooves in the above direction shave off the surface of the drum a plurality of times during one rotation of the drum, thereby obviating filming on the drum.
    Type: Grant
    Filed: October 12, 2005
    Date of Patent: September 19, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Hideo Yoshizawa, Eisaku Murakami, Hiroyuki Nagashima, Yoshiyuki Kimura, Hideki Zemba, Eiji Kurimoto
  • Publication number: 20060177239
    Abstract: An imaging apparatus that is capable of realizing good cleaning characteristics and transfer characteristics, and obtaining a high quality image using toner having a high average roundness is provided. The imaging apparatus includes an image carrier, a charge unit, a developing unit, a transfer unit, and a cleaning unit. The transfer unit may directly transfer a toner image onto a recording medium that is carried by a transfer belt, or transfer the toner image onto the transfer belt first to then transfer the toner image onto the recording medium from the transfer belt. The cleaning unit includes a cleaning blade and a brush roller. The toner used in the imaging apparatus has an average roundness ? within a range of 0.93˜0.99, and a friction coefficient ?s of the image carrier satisfies a condition, friction coefficient ?s?3.6?3.3×average roundness ?.
    Type: Application
    Filed: March 17, 2006
    Publication date: August 10, 2006
    Inventors: Toshio Koike, Eisaku Murakami, Masato Yanagida, Takeshi Shintani, Naohiro Kumagai, Atsushi Sampe, Masami Tomita, Hiroyuki Nagashima, Masanori Kawasumi, Takeshi Uchitani
  • Patent number: 7085528
    Abstract: A cleaning unit cleans residual toner on the surface of a rotatable image carrier. The cleaning unit includes a cleaning blade that is in contact with the image carrier in such a manner that amplitude of a waveform at an edge of the cleaning blade is not greater than 40 ?m with respect to a downstream side of a direction of movement of the image carrier.
    Type: Grant
    Filed: December 3, 2003
    Date of Patent: August 1, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Takeshi Shintani, Naohiro Kumagai, Masato Yanagida, Toshio Koike, Eisaku Murakami, Masanori Kawasumi, Atsushi Sampe, Masami Tomita
  • Publication number: 20060165431
    Abstract: A charging device including a charging roller having a metal cylinder and an elastic layer located thereon, and a cleaner for cleaning the surface of the charging roller. The cleaner includes a driving shaft and a cleaning roller which is rotatably mounted on the driving shaft. The cleaning roller is made of a non-cellular foam resin having a density of from 5 to 15 kg/m3 and a tensile strength of from 1.2 to 2.2 kg/cm2.
    Type: Application
    Filed: March 30, 2006
    Publication date: July 27, 2006
    Inventors: Masato Yanagida, Hiroyuki Nagashima, Naohiro Kumagai, Toshio Koike, Atsushi Sampe, Masanori Kawasumi, Eisaku Murakami, Takeshi Uchitani, Masami Tomita, Takeshi Shintani, Tsutomu Yamakami
  • Patent number: 7065316
    Abstract: A cleaning unit is equipped with a cleaning blade that is in contact with a surface of a photosensitive drum and cleans the surface. A peak temperature of a loss tangent (tan ?) is in a range of 2° C. to ?30° C. when a sine-wave vibration of 10 Hz is applied to the cleaning blade. Moreover, the cleaning unit lowers a coefficient of static friction of the surface of the photosensitive drum that is to be cleaned.
    Type: Grant
    Filed: September 24, 2003
    Date of Patent: June 20, 2006
    Assignee: Ricoh Company, Limited
    Inventors: Masato Yanagida, Atsushi Sampe, Naohiro Kumagai, Toshio Koike, Takeshi Shintani, Masanori Kawasumi, Masami Tomita, Eisaku Murakami, Takeshi Uchitani
  • Patent number: 7062194
    Abstract: A charging device including a charging roller having a metallic cylinder with an elastic layer disposed thereon, and a cleaner for cleaning the surface of the charging roller. The cleaner includes a driving shaft and a cleaning roller rotatably mounted on the driving shaft. The cleaning roller is made of a non-cellular foam resin having a density of from 5 to 15 kg/m3 and a tensile strength of from 1.2 to 2.2 kg/cm2.
    Type: Grant
    Filed: May 12, 2004
    Date of Patent: June 13, 2006
    Assignee: Ricoh Company Limited
    Inventors: Masato Yanagida, Hiroyuki Nagashima, Naohiro Kumagai, Toshio Koike, Atsushi Sampe, Masanori Kawasumi, Eisaku Murakami, Takeshi Uchitani, Masami Tomita, Takeshi Shintani, Tsutomu Yamakami
  • Patent number: 7050741
    Abstract: An imaging apparatus that is capable of realizing good cleaning characteristics and transfer characteristics, and obtaining a high quality image using toner having a high average roundness is provided. The imaging apparatus includes an image carrier, a charge unit, a developing unit, a transfer unit, and a cleaning unit. The transfer unit may directly transfer a toner image onto a recording medium that is carried by a transfer belt, or transfer the toner image onto the transfer belt first to then transfer the toner image onto the recording medium from the transfer belt. The cleaning unit includes a cleaning blade and a brush roller. The toner used in the imaging apparatus has an average roundness ? within a range of 0.93˜0.99, and a friction coefficient ?s of the image carrier satisfies a condition, friction coefficient ?s?3.6?3.3×average roundness ?.
    Type: Grant
    Filed: April 9, 2004
    Date of Patent: May 23, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Toshio Koike, Eisaku Murakami, Masato Yanagida, Takeshi Shintani, Naohiro Kumagai, Atsushi Sampe, Masami Tomita, Hiroyuki Nagashima, Masanori Kawasumi, Takeshi Uchitani