Printing machine and feeding method for printing machines

摘要

Configuration with paired register rollers cooperative with a downstream head unit on a circulation route to register a print sheet, a feed route extending up to the register rollers, and feeder elements controllable for a downstream feed of print sheet along part of the feed route to the register rollers, the feeder elements being controllable for a change of feed speed or acceleration in accordance with information on a back tension of a print sheet on the circulation route.

主权项

1. A printing machine comprising:
an image forming unit adapted for formation of images on a recording medium in course of transfer on a transfer route; a register installed upstream of the image forming unit on the transfer route and adapted for adjustment of a timing to send a recording medium to the image forming unit; a feeder set adapted for feed of a recording medium to the register; a feed route system adapted for connection of feed route through the feeder set to the register; and an assist controller configured to change an acceleration of the feeder set in synchronization with the register in accordance with information on a tension of a recording medium in the feed route system, wherein the assist controller comprises:
a route information database configured to store therein a transfer condition set of the feed route system; andan assist condition calculator configured for acquisition of information on acceleration and deceleration of the register and collation thereof with transfer conditions stored in the route information database, to calculate as an assist condition a slack of a recording medium between the register and a feeder, wherein the assist controller is configured to change an acceleration of the feeder in accordance with the assist condition; and wherein the feed route system comprises: a system of routes each configured for transfer of recording medium to the register; and feeders each configured for feed of recording medium along a corresponding transfer route to the register, and the assist condition calculator is adapted to calculate an assist condition of a respective one of the routes in accordance with transfer conditions thereof, and the assist controller is configured to change an acceleration of a corresponding feeder in accordance with the assist condition, and wherein the system of feed routes includes a re-feed route configured to feed a recording medium to the register from a switchback route branched from the transfer route for a reverse of recording medium.