Scan/Erase Positions - Kodak DirectView CR 800 System Theory Manual

Scan/Erase Positions

There are 4 distinct vertical positions of the EXTRACTION BAR. These positions are monitored by the S9 REFERENCE SENSOR and by ENCODER COUNTS that
are defined when the system is set up at the factory. .
ILlustration of Slow Scan / Reference positions
1234563 – 12/12/94
REFERENCE Position of the EXTRACTION BAR when the S9
SENSOR Position REFERENCE SENSOR is blocked. The REFERENCE
SENSOR position is factory set and varies among
machines.
When the system is initialized, the EXTRACTION BAR
looks for the S9. Once it is located, the EXTRACTION
BAR moves up to the home position where it remains until
the start of a new cycle.
Home Position Position of the EXTRACTION BAR at the start and end of
a cycle.
Home position is between 3.8 and 4.5 cm (1.5 and 1.75 in.)
above the REFERENCE POSITION SENSOR. The home
position is factory set; however, it can be adjusted in the
field if necessary.
Start of Scan Position in the vertical movement of the EXTRACTION
BAR when the NOSEPIECE is engaged, as detected by
Position
the L1 NOSEPIECE CLEAR SENSOR, and the PLATE is
in position to be scanned. Start of scan is a predefined
number of encoder counts below home position.
This defines the mechanical start of scan and differs from
the Optical start of scan which occurs after the MCPU tells
the GALVO to begin scanning the PLATE.
The end of scan is defined by encoder counts based on the
PLATE size.
Erase Position A position below the End of Scan where the PLATE is
centered in front of the ERASE LAMPS. The position
varies depending on PLATE size.
Scan/Erase Subsystem
See "Initialization."
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