Operation Of Sensors And Leds; Paper Entrance / Black Mark Sensor - Hengstler eXtendo X-56 Operating Manual

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eXtendo Thermal Printer Family

3.6. Operation of Sensors and LEDs

3.6.1. Paper Entrance / Black Mark Sensor

There is a sensor in the paper entrance area that serves several functions. First, it
detects paper during paper loading and signals the printer to begin the paper
autoloading function. Similarly, when the printer is out of paper, this sensor detects
the fact and signals the printer accordingly.
The same sensor is also used to detect Black Marks. Black Marks are blackened
areas placed on the paper during the converting process. They are generally used, in
conjunction with appropriate printer commands, to advance the paper to a specific
position after each print job. One common reason for this is to so that preprinted
information is properly located with respect to information printed by the printer itself,
for example, printing inside a preprinted box. Black marks can be located on the
thermally coated side of the paper (where printing takes place) or on the back of the
paper, depending upon the location of the sensor.
The eXtendo
Entrance/Black Mark sensor locations during manufacturing. (The location of this
sensor cannot be changed once the printer is built.) Also, two different sensor types
can be used. The most common is the reflex or reflective sensor, where the light
source and detector are located on a single chip. Basically, the light strikes the white
paper surface and reflects back into the sensor. If enough light reflects to activate the
sensor, the printer concludes that paper is present. If there is not enough light
reflected, the printer assumes that this area is black, meaning the printer is on a black
mark or the printer is out of paper. There are six (6) different possible positions for
this sensor in the X-56 and ten (10) in the X-80. Half of these positions sense the
coated side of the paper, while the other half sense the back of the paper. The
positions of these sensors are detailed in the Paper section of this document.
Part No. D 684 124
Figure 5
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series of printers is designed to allow for numerous Paper
Mod. No. 4 080812 LEV
HENGSTLER
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