A corrugated paperboard sheet feeding apparatus comprises: a plurality of sheet feeding rollers; a grate formed with a plurality of opening portions for receiving the sheet feeding rollers and configured to switch between contact and non-contact states of the corrugated paperboard sheet with respect to the sheet feeding rollers; and a suction box configured to suck the corrugated paperboard sheet downwardly by gaps between the sheet feeding rollers and the opening portions, wherein each of the gaps is formed to be 10 mm or less, and wherein the apparatus further comprises a mat switch for detecting an entry of a person into an area in a sheet feeding section, and a control device for stopping movement of the sheet feeding rollers and/or the grate when the mat switch is turned on.

In a paper feeding apparatus, paper feed rolls in paper feed roll rows for feeding the lowermost one of cardboard sheets placed in a stacked manner on a paper feeding table intermittently one by one toward the printing device are coupled via shafts to separate servomotors. The servomotors are controlled so to be accelerated synchronously and rapidly from a stopped state to a high rotational speed during one cycle of feeding through contact with the lowermost cardboard sheet, while controlled so to be decelerated from the high rotational speed to be stopped rapidly and respectively when determined not to be in contact with the lowermost cardboard sheet.

A corrugated paperboard sheet feeding apparatus comprises: a plurality of sheet feeding rollers; a grate formed with a plurality of opening portions for receiving the sheet feeding rollers and configured to switch between contact and non-contact states of the corrugated paperboard sheet with respect to the sheet feeding rollers; and a suction box configured to suck the corrugated paperboard sheet downwardly by gaps between the sheet feeding rollers and the opening portions, wherein each of the gaps is formed to be 10 mm or less, and wherein the apparatus further comprises a mat switch for detecting an entry of a person into an area in a sheet feeding section, and a control device for stopping movement of the sheet feeding rollers and/or the grate when the mat switch is turned on.