Print medium conveyance device and printing device

Abstract

A print medium conveyance device 40 has a tractor 44, conveyance roller 55, and clutch mechanism 83. The tractor 44 sequentially engages engagement holes formed in a line in the medium and conveys the print medium in a specific conveyance direction X. The conveyance roller 55 is disposed downstream from the tractor 44 in the conveyance direction X, and has a friction layer 59 containing an inorganic particle dispersion formed on the surface. the clutch mechanism 83 is between the conveyance motor 72 and tractor 44, and interrupts transfer of drive power from the conveyance motor 72 to the tractor 44 at least in part under a specific condition. The print medium can therefore be conveyed with high precision while damage to the print medium by excessive tension can be prevented.

Description

technical field [0001] The present invention relates to a transport device for transporting a printing medium having positioning holes (engagement holes), such as fanfold paper, and a printing device provided with the same. Background technique [0002] Such a transport device includes: a tractor sequentially engaged with engaging holes formed in a row on the printing medium to transport the printing medium in a predetermined transport direction; and a transport roller provided near a print head of the printing device. The tractor and the conveyance roller are coupled by a driving force transmission mechanism such as a wheel row or a belt, and are synchronously driven and controlled to convey a predetermined amount of the printing medium at a time (for example, refer to Patent Document 1). [0003] In addition, in order to unfold the printing medium such as fanfold paper from the folded state for easy transportation, the conveying speed of the tractor and the conveying rolle...

AI Technical Summary

Problems solved by technology

However, in the structure in which the tractor and the conveyance roller are coupled via the driving force transmission mechanism as described above, if the slippage of the conveyance roller is excessively suppressed, the conveyance error caused by the state of the printing medium or the conveyance accuracy of the tractor cannot be absorbed by the conveyance roller. Instead, it accumulates, so there is a problem that it cannot meet the requirements of high-precision handling

Moreover, when the tractor is switched from forward to reverse, excessive tension will be applied to the printing medium, and sometimes the printing medium will be broken at the part of the engaging hole where the tractor engages.

Images