Ricoh Company, Ltd.

Takami Suzuki

Nobuo Iwata

Hiromi Takada

Tomoyuki Moriya

Masami Tsunasawa

Takashi Hasegawa

Hiroshi Hosokawa

Hideo Aoki

Takashi Fukushima

Nobuo Sakuma

Hideaki Mochimaru

Yoshiaki Tanaka

Keiji Okamoto

Nobuhiro Makita

Yasuhiro Sagawa

Masayoshi Miyamoto

Masayuki Suzaki

Hiroyuki Idenawa

Takeshi Motohashi

Tadaaki Kanno

Hajime Kanda

Toshio Shimazaki

Takeshi Komurasaki

Satoru Yoshioka

Toshio Shiina

Hisao Ishizu

Koh Matsuhisa

Yoshikuni Tatara

Tadashi Matsuura

Takanori Yamaki

Takahiro Yagisita

Tomoo Sankoda

A mirror surface for deflecting an incident light beam is inclined to the axis of rotation and rotated for scanning the light beam. The incident light beam is applied to the mirror surface along the axis of rotation, and a reflected light beam is continuously deflected by the rotating mirror surface to scan a surface. When the incident light beam has an elliptical cross section in a direction normal to its optical axis, the cross-sectional shape of the reflected light beam varies due to the inclination of the mirror surface in response to rotation of the mirror surface. The varying shape of the reflected light beam obstructs proper reading and writing of an image with a light scanning device employing the above mirror surface. To avoid this problem, light beam shapers are provided in positions before and after the light beam is reflected by the mirror surface.

Light scanning device

A laser printer or like electrostatic recording apparatus of the type developing an electrostatic latent image provided on a photoconductive drum by toner which is conveyed by a developing roller. Various devices of the apparatus including the photoconductive drum and developing roller are separated into an upper and a lower unit which are openable away from each other. A photoconductive drum assembly including the photoconductive element and a developing assembly including the developing roller are individually detachable from a body of the apparatus. Various measures are taken to enhance stable and safe operation, miniaturization, easy maintenance, operability, service life, and image quality.

Electrostatic recording apparatus

A hybrid printer includes at least one impact type print head and at least one non-impact type print head, which are selectively used to print not only graphic information but also character information. For example, the impact type print head may be a type wheel print head and the non-impact type print head may be a pen print head. The print heads are selectively magnetically coupled to the carriage drive belt.

Selective magnetic attachment of a print head to a drive belt

A type carrier for use in an impact-type printing machine to form an imprint of virtually the equal quality when used with either a flat hammer or a detentable, shaped hammer is provided. The present type carrier includes a hub and a plurality of fingers extending from the hub, each finger having a printing section which has a front surface provided with at least one type and a back surface having a novel structure. The back surface of the printing section includes at least one flat portion and at least a pair of sloped portions. Preferably, the sloped portions are defined such that they slope down oppositely from a plane common to or below the flat portion in the direction substantially perpendicular to the lengthwise direction of the finger.

Type carrier for use in impact-type printing machines

A print wheel mounting assembly for a serial printer comprising means for transmitting a torque from a rotary shaft to a print wheel, means for positioning the print wheel in the direction of its rotation and means for regulating the position of the print wheel axially thereof, whereby no special tool is required for mounting or detaching the print wheel on the rotary shaft.

Print wheel mounting assembly for serial printer

Each of resilient tongues of a type wheel for use in a serial printing apparatus carries one or more type members. Each of the type members is provided with a curved or concave type face whose center of curvature lies on an axis of a paper supporting platen so that the type face comes into even and tight contact with the platen surface in a printing position. The curved type face is formed on a projection having a forward end which is tapered toward or away from a plane perpendicular to a rotary axis of the type wheel. Further, the each of the type members is provided with a back face which is formed on a back portion of the curved type face. The back face is driven by a hammer which is oriented in a predetermined direction toward the axis of the platen so as to be evenly and entirely engaged with a striking face of the hammer in the printing position. The back portion of the curved type face comprises a projection which is tapered toward or away from a plane perpendicular the rotary axis of the type wheel. The back face is so inclined as to be parallel to a direction perpendicular to the predetermined direction of the hammer in the printing position.

Type wheel for serial printing apparatus

Resilient tongues project from a central hub and carry two or more type members. The hub is rotated to a position in which the tongue carrying the desired type member is in a printing position facing a paper supporting platen. The hub is then shifted along the axis of the selected tongue so that the required type member is in a printing position. A drive motor for rotating the hub is connected to the hub by a universal joint to compensate for the shifting of the hub. The universal joint comprises a biased presser member to eliminate lost motion in the rotational direction. A stopper member is provided so that the bending characteristics of the selected tongue are the same no matter which type member is selected. A hammer drives the type member against the paper to print. The resilient tongues are formed of a thermoplastic resin mixed with glass or carbon fibers and the type members may be formed separately from the tongues, fixed thereto and plated with metal. The hub may be formed in two or more sections, with each section carrying some of the resilient tongues. The tongues are bent in such a manner that all of the type members lie in a common plane. The angles between the type members and the tongues are selected in such a manner that all of the type members strike the paper perpendicular to the platen.

Method of making rotary type wheels

Serial printing apparatus

A type wheel comprises a rotary hub, a plurality of resilient, circumferentially spaced arms extending radially outwardly from the hub and a plurality of type elements provided at the end portions of the respective arms. The type wheel is rotated until the selected type element reaches a printing position relative to a platen. One or more sheets of paper interspersed with carbon sheets are wound around the platen for printing. A lever is positioned to adjust the distance between the type wheel and the platen in accordance with the number of sheets. A printing hammer is electromagnetically actuated to resiliently move the selected arm so that the respective type element impacts against the paper through an inked ribbon to print the desired character. The length of time required for the hammer to clear the non-selected arms of the type wheel after impact is a function of the number of sheets of paper and thereby the position of the lever. An electrical circuit computes this length of time and inhibits rotation of the type wheel thereduring.

High speed impact printer

A driving mechanism for the carriage of a printer, having a motor with a driving pulley thereon, which has attached to it the ends of left and right cables, each of which is folded at its respective center. The folded portions of the cables are wrapped on a pair of pulleys mounted on the carriage.

Carriage driving mechanism for printer

Growing community of inventors

Yokohama, Japan

Takami Suzuki