Carrier Stop Mechanism
Disclosed is
a method which controls the positioning of the
printing head carrier by using an optical sensor to eliminate the
risk of "dog ear" on the passbook printer.
Fig. 1 shows
an example of this device. The printing
head
carrier (1) on the passbook printer has the printing head gap roller
(2) and the paper guide (3). The
printing head gap roller runs on
papers bi-directionally to print and the paper guide helps the paper
to load between the platen (4) and the roller.
For paper feed, the
printer head gap roller sidesteps on
either right or left.
The right
positioning of the roller when sidestepping is a key
issue. Traditionally, on many passbook
printers, the printing head
gap roller sometimes overruns to the point where the paper is
completely away from the printing head and the paper guide is no
longer effective, which eventually
causes a "dog ear" problem.
This
problem is more often observed when
loading partially-curled or thin
papers.
The M/T 9068
passbook printer shown in Fig. 2 detects the
positions of both edges of the paper by scanning left-to-right before
printing with the optical sensor (5) attached to the printing head
carrier. Based on the information, the
printer sets the positions
where the head carrier sidesteps at both ends.
Currently, the
positions are within 20mm from the
paper, so that the paper guide
function works.
Given the
great advantage of this n...