1
Susumu Tatsumi, Masumi Ikesue, Masao Hosaka, Nobuo Kasahara: Electrostatographic apparatus comprising automatic document type determination means. Ricoh Company, David G Alexander, December 16, 1980: US04239374 (55 worldwide citation)

An image of an original document (16) is sensed to determine if the document (16) is a printed document (the image consists of characters and symbols) or a photographic document. The exposure illumination intensity, developing bias voltage and/or other variable operating parameters are controlled in ...


2
Seiichi Miyakawa, Susumu Tatsumi, Koji Sakamoto: Method of maintaining the correct conditions of an electrophotographically duplicated image. Ricoh Company, Oblon Fisher Spivak McClelland & Maier, August 5, 1980: US04215930 (51 worldwide citation)

A method of maintaining the correct conditions of an electrophotographically duplicated image, which uses a reference plate having at least a dark-tone area and a light-tone area and in which signals associated with the reference plate are detected and synthesized to control the duplicating process ...


3
Koji Sakamoto, Susumu Tatsumi, Chikara Imai: Electrostatographic apparatus comprising document density sensing means. Ricoh Company, David G Alexander, April 29, 1980: US04200391 (47 worldwide citation)

Prior to optical scanning of an original document (14) for producing an electrostatic image thereof on a photoconductive drum (12), the optical density of the document (14) is sensed and a light image intensity and a developing bias voltage are set in accordance with a sensed minimum or background d ...


4
Koji Sakamoto, Seiichi Miyakawa, Susumu Tatsumi: Electrostatic copying machine. Ricoh Company, Jordan and Hamburg, October 7, 1980: US04226525 (46 worldwide citation)

An exposure unit radiates a light image of an original document onto a charged photoconductive member to form an electrostatic image through localized photoconduction. A developing unit applies a powdered developing substance comprising carrier particles and toner particles to the photoconductive me ...


5
Masumi Ikesue, Takashi Yano, Susumu Tatsumi, Hiroyuki Idenawa, Isao Nakamura, Tatsuo Tani: Variable magnification electrostatic copying machine. Ricoh Company, David G Alexander, July 7, 1981: US04277163 (44 worldwide citation)

The vertical and horizontal lengths of an original document (28) are automatically sensed and compared with the vertical and horizontal lengths of a copy sheet (38) and the reduction ratio of a variable magnification optical system (33) is automatically adjusted in accordance therewith so that the m ...


6
Koji Sakamoto, Seiichi Miyakawa, Susumu Tatsumi: Exposure control and other component control for electrostatic copying machine. Ricoh Company, Jordan and Hamburg, December 22, 1981: US04306804 (30 worldwide citation)

An exposure unit radiates a light image of an original document onto a charged photoconductive member to form an electrostatic image through localized photoconduction. A developing unit applies a powdered developing substance comprising carrier particles and toner particles to the photoconductive me ...


7
Susumu Tatsumi, Tadahiro Eda, Chikara Imai: Copy image adjustment method. Ricoh Company, McGlew and Tuttle, July 7, 1981: US04277549 (26 worldwide citation)

In an electrophotographic copying machine, the copy image adjustment method for correcting copy image characteristics comprises the steps of measuring copying characteristics by use of a reference original and resetting development characteristics in accordance with the measurement results.


8
Koji Sakamoto, Seiichi Miyakawa, Susumu Tatsumi: Apparatus for sensing deterioration of developing substance including ferromagnetic carrier and non-magnetic toner particles. Ricoh Company, Frank J Jordan, March 25, 1980: US04195260 (21 worldwide citation)

Deterioration of a dry developing substance causes toner particles to be so strongly adhered to carrier particles that they cannot be readily separated therefrom. The present apparatus comprises means for applying a predetermined electrostatic or air suction force to the developer to readily remove ...


9
Tsuneo Kurotori, Manabu Mochizuki, Susumu Tatsumi: Process for treating exhaust gas from electrophotographic machine and apparatus thereof. Ricoh, Flynn Thiel Boutell & Tanis, November 15, 1983: US04415533 (19 worldwide citation)

A process for treating exhaust gas from an electrophotographic machine which comprises oxidizing, in the presence of a heated oxidation catalyst, an odorous exhaust gas generated in course of the steps of developing an element being developed by means of a developer, transferring the thus developed ...


10
Tatsuo Tani formerly Nishikawa, Susumu Tatsumi, Mitsuo Tanaka, Sakae Ota, Akira Midorikawa: Construction of electrophotographic copying machines with a cleaning unit for photosensitive surface. Ricoh, McGlew and Tuttle, June 28, 1977: US04032229 (19 worldwide citation)

The electrophotographic copying machines are of the type in which a photosensitive drum is removable from the machine, for inspection or other purposes, through an opening formed in a sidewall, which opening is normally covered by a coverplate. Plural cleaning devices which are normally maintained i ...



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