HP 220 - Manual (Page 34)

5Ć2 Functional Overview C3187Ć90000
Loading the Media
Entry Platen
The media load path begins with the entry platen, which provides a loading surface.
(Illustration ' page 10Ć23.)
When you assemble the plotter, it is important to correctly position the entry platen to ensure
that the dashed lines exactly indicate the permitted rightĆedge loading area. The left side of
the entry platen should be pressed up against the left sideĆplate. (Details ' chapter 6.)
(Loading Instructions ' User's Guide, chapter 2, w Loading media.)
Sensing Media Presence
Media Sensor
The media sensor is an optosensor and is mounted towards the right end of the entry platen.
(Illustration ' page 10Ć23). Two articulated levers block the optical path between emitter
and receiver when media is not loaded. When media is loaded, both levers are rotated, thus
clearing the optical path and changing the sensor state from open to closed. This
doubleĆlever system provides a leading and trailing edgeĆsensing capability (for mediaĆlength
measurement) to the plotter. The media sensor is electrically connected to the main PCA.
1. Media Not Loaded
Primary flag
Secondary flag
Drive roller
stopped
Sensor housing
Photo sensor area
(cross-section)