Spin Motor; Mirror; Encoder; Linear Carriage Transport Overview - AGFA Avantra 36/44 Service Manual

2.12.1 Spin Motor

The spin motor is a precision hydrostatic (air bearing) spindle DC servo motor.
Refer to Figure 2-8. It runs at a constant velocity of 13,500 RPMs for Avantra 36/44
systems and 20,000 RPMs for Avantra 36S/44S systems.

2.12.2 Mirror

The 42.5 degree spin mirror deflector attaches directly to one end of the spin motor
shaft. Refer to Figure 2-8. The mirror reflects the converging beam from the spot
generation module 95.0 degrees away from the spin axis, and sweeps the focused
spot around the internal circumference of the drum, exposing the media.

2.12.3 Encoder

The encoder is a 1000 line rotary type encoder, balanced and attached to the oppo-
site end of the motor shaft. Refer to Figure 2-8. The encoder is the master clock
source for the fast scan modulation of the laser diode, as well as the master clock
for the slow scan carriage drive. Both clocks operate through Phase Lock Loop
(PLL) systems to average the noise and errors in the encoder disk. The encoder also
has a once/rev or index sensor used to synchronize all of the opto/mechanical
components. This signal generates the Beginning of Line (BOL) signal.

2.13 Linear Carriage Transport Overview

The linear carriage transport components support the optical system, as well as
provide the precise translation of the optical system along the axis of the internal
drum.
The major components are:
•

Carriage assembly

• Linear bearing guideway
• Carriage home position sensor
2.13.1 Carriage Assembly
The carriage assembly, which is a field replaceable unit, traverses through the cen-
ter of the drum on rails. The carriage assembly supports and translates the optical
system through the internal drum. Figure 2-9 illustrates the carriage assembly.
Section I: Imagesetter
Functional Analysis 2-19