Patent ID: 9694610
Date: 2017-07-04
CPC Classifications: B41J

Claim:
1. An automatic web threading method of an inkjet printer that carries out printing by an inkjet method with respect to a long Z-folded continuous paper provided with a perforation at every page break and provided with marginal punch holes in both sides, the inkjet printer comprising: a paper feeding unit that disposes the Z-folded continuous paper; a first pull roller, an intermediate pull roller, and a second pull roller for conveying the continuous paper; a first pin tractor and a second pin tractor for carrying out positioning of the continuous paper; a printing unit that carries out printing on the continuous paper by a print head; and a discharging unit that Z-folds and discharges the continuous paper by a folding machine; wherein, each of the first pin tractor and the second pin tractor has pins and carries out positioning of the continuous paper by inserting the pins in the marginal punch holes; a driving motor is attached to the first pin tractor via a clutch; the driving motor is directly attached to the second pin tractor; the second pin tractor is movable so as to become a state in which the pins are removed from the marginal punch holes from a state in which the pins are inserted in the marginal punch holes; a paper detecting sensor for detecting a front end of the continuous paper is attached to a side opposed to the second pin tractor via the continuous paper; a first detachable gripper roller for sandwiching the continuous paper abuts the first pull roller, a third detachable gripper roller for sandwiching the continuous paper abuts the intermediate pull roller, a second detachable gripper roller for sandwiching the continuous paper abuts the second pull roller, and driving motors are respectively attached to the first pull roller, the intermediate pull roller and the second pull roller; and, in a conveyance path of the continuous paper, the first pin tractor, the first pull roller, the printing unit, the intermediate pull roller, the second pin tractor, and the second pull roller are disposed in this order from an upstream side; the automatic web threading method comprising the steps of: a first step of inserting the pins of the first pin tractor in the marginal punch holes of the continuous paper; a second step of connecting the clutch, driving the first pin tractor by the driving motor, conveying the continuous paper until the front end of the continuous paper is detected by the paper detecting sensor, and then stopping driving of the first pin tractor by the driving motor; a third step of causing the detached third gripper roller to abut the intermediate pull roller, sandwiching the continuous paper between the intermediate pull roller and the third gripper roller, conveying the continuous paper to the upstream side at an extremely low speed by the intermediate pull roller, and applying tension to the continuous paper that is between the intermediate pull roller and the first pin tractor; a fourth step of inserting the pins of the second pin tractors in the marginal punch holes of the continuous paper; a fifth step of disconnecting the clutch so that the first pin tractor follows conveyance of the continuous paper, driving the second pin tractor by the driving motor, and conveying the continuous paper to the discharging unit; a sixth step of moving the second pin tractor in order to remove the pins from the marginal punch holes; and a seventh step of sandwiching the continuous paper between the first pull roller and the first gripper roller abutting the first pull roller and between the second pull roller and the second gripper roller abutting the second pull roller and conveying the continuous paper.