Ryobi Limited

Hiroyuki Sarada

Katsushi Hirokawa

A sheet-holding-down member provided in a sheet feeding section of a printing press has a sheet-holding-down member that has a sheet-holding-down part that holds down from above an oncoming sheet to prevent a lateral edge of the sheet from being curled upward when the sheet abuts a lateral-edge abutment member. The sheet-holding-down member is pivotally movable about a roller support shaft so as to allow the sheet-holding-down part to be movable close to and away from an upper surface of a feeder board, on which the sheet is placed. An adjustment screw has a lower end that limits movement of the sheet-holding-down member so as to prevent the same from moving close to the upper surface of the feeder board as passing a predetermined height limit. The sheet-holding down member is urged downward by a coil spring. In a case where a sheet having a thickness larger than a predetermined thickness is used, the sheet-holding-down member is pivotally moved upward against the urging force of the coil spring, thereby allowing the sheet-holding-down part to move upward away from the upper surface of the feeder board.

Sheet positioning apparatus in a sheet feeding section of a printing press

A sheet-fed printing press includes stationary guide means for guiding said control cams in the axial direction of the turn-over drum, switching cam followers respectively provided on the control cams in such a manner as to protrude radially outwardly therefrom, sliders respectively forming therein camming recesses to be respectively engaged with said switching cam followers, and a slider driving means for reciprocatingly driving the sliders in such a manner as to enable the switching cam followers to reciprocatingly travel in the axial direction of the turn-over drum. The switching cam followers each travel from a first end to a second end of a corresponding one of said camming recesses along the longitudinal axis thereof for switching to the both-side printing operation, and each travel from said second end to said first end of said corresponding one of said camming recesses along the longitudinal axis thereof for switching to the single-side printing operation. The first and second ends along the longitudinal axis of each camming recess respectively have end walls adapted to press a corresponding one of said switching cam followers, so that the control cams are respectively biased against the stationary guide means in the direction substantially orthogonal to the axial direction of the turn-over drum.

Sheet-fed printing press capable of printing both sides of a sheet

A cam shaft 23 is rotated 90 degrees when the plate 10 is fitted on the plate cylinder 60. Thus, as a result of the rotation, a flange part 3T of the tail edge side clamping base 3 is pushed by movement of a spring base 15 which receives a pushing force generated by springs 16. Therefore, the plate 10 is pulled in a tension applying direction. Since the tail edge side clamping base 3 does not receive the limitation of the cam shaft 23 directly, the tail edge side clamping base 3 can be moved in a direction parallel to a shaft of the plate cylinder 60. Thus, a diagonal image adjustment of the plate can be done easily.

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Fuchu, Japan

Hiroyuki Sarada