Custom Audio Electronics KPM180H, Руководство пользователя

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7 ALIGNMENT
The device is provided with sensors for the use of alignment black mark in order to handle:
•
roll of tickets with pre-printed ields and a ixed length;
•
Fan-fold of tickets with pre-printed ields and a ixed length.
The alignment black mark may be formed by:
•
a black mark printed on paper (see paragraph 9.10
);
• a hole between two tickets (see paragraph 9.10 ).
All alignment sensors are “relection” sensors: this kind of sensor emits a band of light and detects the quantity of light
relected to it. The presence of the black mark is therefore detected by the amount of light that returns to the sensor, con
-
sidering that the light is relected by the white paper and absorbed by the black mark.
To use tickets with holes, it is possible to use the same sensors as “transparence” sensors, coupled two by two: a beam of
light is emitted by the transmitter sensor and the quantity of light which reaches the opposite receiver sensor is detected.
The presence of the hole is detected evaluating the amount of light that arrives to the opposite sensor, considering that the
paper doesn’t allow the beam of light to reach the receiver, whereas a hole lets the light to reach the receiver.
The following paragraphs show how to correctly set the coniguration parameters of device in order to assure the alignment.
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