Tohoku Ricoh Co., Ltd.

Ricoh Company, Ltd.

Kazuyoshi Kobayashi

Tomiya Mori

Kengo Tsubaki

Masanori Takahashi

Tetsuo Tanaka

Takayuki Onodera

Toshimitsu Okubo

Kohki Ohmura

Nobuyuki Hoshi

Yukihiko Yoshino

Yoshinobu Sai

Toshiaki Sannohe

Sigenobu Irokawa

Takuo Satoh

Yasuo Endoh

A stencil printer of the present invention includes a printer body, a print drum rotatably mounted on the printer body, a press roller for pressing a sheet against the circumferential surface of the print drum, and a moving device for selectively moving the press roller into or out of contact with the outer circumference of the print drum. The press roller and moving device are capable of being pulled out from the printer body integrally with each other.

Stencil printer with pressing member and moving device integrally movable out of printer body

A stencil printer of the present invention includes a print drum and a pressing member selectively movable into or out of contact with the print drum. A duplex master, formed with a first and a second image in the lengthwise direction thereof, or a simplex master formed with a third image is wrapped around the print drum in a duplex mode or a simplex mode, respectively. The stencil printer is capable of selectively performing a duplex print mode operation, which consists of a front printing step and a rear pining step following the front printing step, or a simplex print mode operation. When the operator of the printer selects the duplex print mode to cause the duplex master to be wrapped around the print drum and then replaces the duplex print mode with the simplex print mode, the stencil printer produces an alarm and inhibits the simplex pint mode operation from being started.

Stencil printer

A stencil printer of the present invention includes a print drum for wrapping a master therearound, a master making and conveying section for perforating a stencil paid out from a stencil roll while conveying it to thereby produce the master, a master stocking section for stocking the master being conveyed by the master making and conveying section, and a roller pair for conveying the master out of the master stocking section. A movable master guide selectively guides the stencil paid out from the stencil roll to the master stocking section or the roller pair. A stretching member adjoins the print drum and is movable between a contact position where it contacts the stencil present on the print drum to thereby exert a stretching force on the master and a released position where the former is released from the latter. The stretching member and movable master guide are interlocked to each other.

Provided are a stencil printing method and an apparatus therefor, in which a master having a low stiffness such as a single film may be transferred, in which a complicated mechanism for fitting and removing a plate is not needed and in which a degree of avoiding movement of a pressing roller to be in contact with the master can be minimized. The printing method and apparatus are characterized in that a perforated thermoplastic resin film is fed from a feeding roller and is brought into contact with an ink permeable sheet mounted under a tension for constituting a printing surface, in that a printing paper is superposed on the film, in that an ink roller having a printing ink from an inking section disposed on a surface of the ink permeable sheet opposite the film is displaced relative to the ink permeable sheet and the film while being maintained in rolling contact with the ink permeable sheet, thereby to perform the printing, and in that the ink permeable sheet, the film and the inking section are thereafter returned to their print starting state.

Stencil printing method and device

In a stencil printer including a rotatable drum for wrapping a perforated stencil or master therearound, a pair o f inclined tension rollers are movable into and out of contact with the drum in order to smooth a creased master. The distance between the tension rollers sequentially increases from the upstream side toward the downstream side with respect to an intended direction of master transport. While the master is sequentially wrapped around the drum, the tension rollers pull the opposite side edges of the master outward. At the same time, the elastic member presses the intermediate portion of the master. The tension rollers and elastic member cooperate to smooth the master. The elastic member is located at a position not closer to the drum than a position around a line connecting the points of the tension rollers contacting the master, and where it can contact the intermediate portion of the master.

In a stencil printer, a drum has the outer periphery thereof formed by a porous sheet having passages for ink therein. The passages are each configured such that the ink entered an inlet pore is diverted from a single perpendicular to the drum at least once, and then flows out via at least one of outlet pores. The pores of the sheet are sized smaller than perforations to be formed in a stencil.

Structures of a drum and a stencil for a stencil printer

An offset printer having a printing section and a plate making section in a unitary assembly. The plate making section is located above the printing section. The printing section includes a plate drum, a rubber drum, and a press drum. The press drum is disposed above and at a predetermined angle relative to the rubber drum. The diameter of the press drum is at least two times as great as the diameter of the rubber drum.

Growing community of inventors

Miyagi, Japan

Kazuyoshi Kobayashi