| 摘要 |
A sheet paper feeder for use in a printing press, includes a cam mechanism (43, 49) interposed between sheet feeding rollers (79), and a source of drive force for the sheet feeding rollers (79) which are adapted to be repeatedly rotated and stopped along a programmed continuous cam operation curve. A retracting mechanism associated with sheet holddown wheels (80) operates in synchronism with the sheet feeding rollers (79) to cause reciprocating movement of the sheet holddown wheels (80) toward and away from the sheet feeding rollers (79). An accurately registered sheet is held between the sheet feeding rollers (79) and the sheet holddown wheels (80) while the sheet feeding rollers (79) are stationary, and the sheet feeding rollers (79) are then accelerated up to a predetermined peripheral speed so that, even if the sheet has a slippery surface, or, the sheet feed rate exceeds 100 sheets per minute, the sheet can be accurately and reliably fed in synchronism with the operation of the printing press without causing any slip between the sheet feeding rollers (79) and the sheet. |
