Detectors - Star Micronics NX-1020 Technical Manual

THEORY OF OPERATION

4-5. Detectors

(1) Home Position Detector
A photo-interrupter is used in the home position detector, which is set at the left side of the frame unit.
ON/OFF signals are generated according to the position of the shield plate mounted at the base of the carriage, and
the printing position is determined by these signals.
(2) Paper End Detector
A paper end detector is located at the paper insertion slit. When paper is present, the photo transistor with the
reflecting type photo sensor goes on. As soon as paper runs out, this transistor goes off, outputting a paper empty
signal.
Fig. 2-24 Home Position Detector
(3) Tractor Position Detector
The leaf switch is open when the tractor is used in pull-tractor mode, and it is closed when the tractor is used in
push-tractor mode.
(4) Release Lever Position Detector
The leaf switch is open when the release lever is in the friction position, and is closed in the tractor position.
Fig. 2-26 Tractor Position Detector
Fig. 2-25 Paper End Detector
Fig. 2-27 Release Lever Position Detector
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