Ricoh Company, Ltd.

Rei Suzuki

Kyohta Koetsuka

Noriyuki Kamiya

Hiroya Abe

Takashi Innami

Masayuki Ohsawa

Yoshiyuki Takano

Tadaaki Hattori

Toshio Kojima

Mieko Terashima

Mieko Kakegawa

Masashi Nakayama

Yuusuke Arai

Soichiro Fukutomi

Yuki Moro

Mieko Kakegawa/Terashima

A roller includes a cylindrical body having openings on both ends thereof and a press-fit member fitted in at least one of the openings of the cylindrical body with an outer circumferential face thereof in contact with an inner face of the cylindrical body. The outer circumferential face of the press-fit member is grooved obliquely to an axis of the cylindrical body, and the inner face of the cylindrical body is smooth at least in a portion that contacts the outer circumferential face of the press-fit member.

Roller, developing roller, developing device, process cartridge, and image forming apparatus

An image forming device comprises a process cartridge. The process cartridge comprises a development roller. The development roller comprises a magnet roller and a developing sleeve. The magnet roller is fixed. The depressionseach having an oval shape are formed on the external surface of the developing sleeve. Both ends of the depressionswhich are adjacent with each other along the longitudinal direction of the developing sleeveare overlapped with each other and both ends of the depressionswhich are adjacent with each other along the circumferential direction of the developing sleeveare spaced with each other.

Development roller, development device, process cartridge and image forming device

A developing roller includes a developing sleeve and a magnet roller disposed within the developing sleeve to attract developer to an outer surface of the developing sleeve by magnetic force. The outer surface of the developing sleeve has a plurality of recesses of circular or elliptic shape in plan view regularly or irregularly arranged therein so as not to overlap.

Developing roller, developing device, process cartridge, and image forming apparatus

A magnetic field generating member with high stiffness and small size, an image development device, a process cartridge and an image forming apparatus including the magnetic field generating member as well as a manufacturing method of the magnetic field generating member are provided where the magnetic field generating member includes a main body, a groove provided in the main body, an interposition member configured to be fitted in the groove of the main body and including a concave portion and a magnetic member as a long magnetic compact fixed into the concave portion of the interposition member.

Magnetic field generating member and manufacturing method thereof, magnetic particle support body, image development device, process cartridge and image forming apparatus

A developer carrier includes a magnetic field generating device provided with a plurality of magnetic poles including an agent separating pole and a scooping pole, and a cylindrical hollow body accommodating therein the magnetic field generating device and rotated around an axis of the cylindrical hollow body. A half-value width of a magnetic flux density at both end portions of at least one magnetic pole of the agent separating pole and the scooping pole is formed to be identical to or narrower than a half-value width of the magnetic flux density at a central portion of the one magnetic pole.

Developer carrier, development device, process cartridge, and image forming apparatus

A magnetic roller includes a cylindrical magnetic field generation part (), a cylindrical support part () that contacts both of the edges of the magnetic field generation part (), further has a smaller diameter than the magnetic field generation part (), and which is installed upon a common axis thereof as an axis of the cylindrical support part (), and a depression part () that is installed upon an obverse surface of the cylindrical magnetic field generation part (), extends in a direction of the axis of the magnetic field generation part (), and wherein a lengthwise magnet formation is inserted. The cylindrical magnetic field generation part () is configured of a main body portion (), which is installed upon a central portion of the cylindrical magnetic field generation part (), and a reinforcing portion (), which is installed upon each of both ends, wherein the depression part () is installed across the main body portion () of the magnetic field generation part () overall, and the reinforcing portion () is installed between an end of the depression part () and an end of the support part.

Growing community of inventors

Atsugi, Japan

Rei Suzuki