Riso Kagaku Corporation

Masaharu Ogata

Akira Yasuda

Koji Nakayama

Hideaki Takayama

A stencil printing machine of the present invention has an inner press roller ( ) arranged in the inside of a printing drum ( ), an inner press mechanism ( ) for shifting the inner press roller ( ) between a pressure position (B) and a standby position and for adjusting a pressure power of the inner press roller ( ) at the pressure position (B). At the pressure position (B), the inner press roller ( ) presses the inner peripheral surface of a screen ( ) forming a peripheral wall of the printing drum ( ). At the standby position, the inner press roller ( ) is separated from the inner peripheral surface. During printing, the inner press roller ( ) is positioned at the pressure position (B) at which the inner press roller ( ) presses the inner peripheral surface of the screen ( ). The inner press mechanism ( ) has an ink supply unit ( ) arranged at the inside of the printing drum ( ) in order to shift the inner press roller ( ) between the pressure position (B) and the standby position. A power transfer section ( ) is arranged in the outside of the printing drum ( ). The power transfer section ( ) transfers the driving power to the ink supply unit ( ) in order to shift the inner press roller ( ) between the pressure position (B) and the standby position and also in order to adjust the pressure power of the inner press roller ( ) at the pressure position (B).

Stencil printing machine

According to the stencil printing machine of the present invention, ink that has entered the gap between a circumferential wall and a stencil sheet is allowed to escape to the outsides of an inner pressing roll in the axis direction. When it reaches the outer circumferential face of an ink free passage section of a screen, the escape ink is allowed to pass through the ink free passage section by a pressing force from the pressure drum, and directed to the inner circumferential side; therefore, it is possible to prevent the escape ink from reaching the right and left ends of the stencil sheet, and consequently to eliminate the limitation to the number of prints in endurance printing processes that is imposed due to ink leakage from the stencil. Moreover, since it is not necessary to form a raised portion along the circumferential face, the printing drum can be easily manufactured at low costs.

A pressure printing apparatus in which a printing sheet is pressed against a stencil sheet, the pressure printing apparatus includes: a printing sheet table having a printing sheet holding surface inclined vertically; a sheet slidable member provided on the printing sheet holding surface of the printing sheet table, for sliding the printing sheet down from the printing sheet table; a gate for selectively holding the printing sheet fed onto the printing sheet holding surface of the printing sheet table on the printing sheet holding surface; a stencil sheet support portion disposed above and in opposition to the printing sheet table, for supporting the stencil sheet; a pressing member for pressing the printing sheet table against the stencil sheet support portion; and a printing sheet release frame provided between the printing sheet held by the printing sheet table and the stencil sheet supported by the stencil sheet support portion, for releasing the printing sheet stuck to the stencil sheet from the stencil sheet.

Growing community of inventors

Ibaraki-ken, Japan

Masaharu Ogata