Abstract: A stencil printer includes a printing drum which has an ink-permeable peripheral wall and is rotated about a predetermined axis of rotation with a stencil master wound around the peripheral wall, a back press roll which associates with the printing drum to nip and convey a printing paper, and an internal press roll which is provided in the printing drum to be movable back and forth toward and away from the back press roll and pushes the peripheral wall of the printing drum toward the back press roll. An internal press roll drive mechanism moves back and forth the internal press roll between a first position where the internal press roll is held away from the back press roll and a second position at a distance from the first position toward the back press roll and is able to freely change the distance between the axis of rotation of the printing drum and the second position.

Abstract: A stencil printing machine includes a squeegee roller in a printing drum having a peripheral wall having an ink-nonpermeable nonperforated portion around an ink-permeable perforated portion to have a stencil sheet and a printing the print sheet therearound. A projected portion is provided on the nonperforated portion. The thickness of the nonperforated portion is formed thicker than that of the perforated portion, and accordingly, press force exerted to the peripheral wall and the stencil sheet by the squeegee roller and the outer roller is enhanced on the nonperforated portion. Therefore, spread of ink is stopped within the perforated portion and ink is prevented from leaking from a gap between the outer peripheral face of the nonperforated portion of the peripheral wall and the stencil sheet.

Abstract: Disclosed herein is a stencil printer including a rotatable paper pinch drum with a cutout, a plurality of printing drums, and a position control unit. The cutout is formed in a portion of the outer peripheral surface of the rotatable paper pinch drum along a generating line in the axial direction of the drum. The plurality of printing drums have axes parallel with an axis of the paper pinch drum and disposed around and near the paper pinch drum so that the printing drums rotate in synchronization with the paper pinch drum in the opposition direction from the direction of rotation of the paper pinch drum. Each of the printing drums includes a stencil paper clamper which clamps one end of a paper stencil wound around the outer peripheral surface of the printing drum and an internal press roller which supplies ink to the stencil paper.

Abstract: According to the stencil printing machine of the present invention, the printing drum unit is moved from a side direction to the pulled-out first support rail so that the one support rod is supported. That is, unnecessary becomes the operation of holding up the printing drum unit once upwards and then bringing down the unit. Moreover, the one support rod is supported so that the printing drum unit is provisionally supported. Thus, this unit can be supported by one hand. In this state, the second support rail is pulled out and the other support rod is supported by the second support rod, so that the pair of the support rods is supported by the first and second support rails. In this way, setting-up of the printing drum unit is completed.

Abstract: A stencil printing machine incorporating squeegee roller in printing drum having peripheral wall having ink-nonpermeable nonperforated portion around ink-permeable perforated portion for winding a stencil sheet and printing the print sheet while transferring the print sheet by sandwiching the print sheet between the printing drum and the outer roller, wherein projected portion is provided on the nonperforated portion constituting side of inner peripheral face of the peripheral wall, thickness of the nonperforated portion is formed thicker than thickness of the perforated portion and accordingly, press force exerted to the peripheral wall and the stencil sheet by being sandwiched by the squeegee roller and the outer roller is enhanced on the side of the nonperforated portion and therefore, spread of ink is stopped within range of the perforated portion and ink is prevented from leaking from gap between outer peripheral face of the nonperforated portion of the peripheral wall and the stencil sheet.

Abstract: An image forming machine includes an image forming section for receiving a sheet supplied in a supplying direction, printing an image on the sheet, and discharging the printed sheet in a discharging direction opposite to the supplying direction while changing the sheet upside-down; a sheet supplying table situated adjacent to the image forming section, the sheet supplying table stacking the sheet to be supplied to the image forming section; a sheet discharging table situated adjacent to the image forming section and disposed vertically relative to the sheet supplying table, the sheet discharging table stacking the sheet having the image printed thereon and discharged from the image forming section; driving mechanism attached to the sheet supplying table and the sheet discharging table for vertically moving the sheet supplying table and the sheet discharging table in directions opposite to each other.