| 摘要 |
Apparatus for feeding individual cardboard sheets to a rotary die cutting machine has two conveyor systems. The first system conveys a sheet from the bottom of a stack to a gap in a gate which passes only one sheet, and the second system conveys the sheet from the gap to the machine. Each system includes a perforated belt traveling in a closed loop over a suction box near the gate. The belt of the first system is shifted cyclically between an operative position of simultaneous engagement with the associated suction box and the bottom sheet of the stack and a retracted position and is accelerated and decelerated between a minimum speed in the retracted position and a maximum speed in the operative position, air being drawn from its suction box only in the operative belt position. The belt of the second system is driven continuously at a speed approximately equal to the maximum speed of the other belt, and air is drawn from its suction box only when the first belt is in the retracted position. |
