Service manual

3 • Theory Of Operation
DM300c/DM400c/DM475 Service Manual (SV61801 Rev. D)
3-43
Motor Summary
Tape Motor. The tape motor is an integral part of the tape feed unit. See
Figure 3-4A. It feeds tape strips from the feed chute into the tape path of the
mail transport. It is a stepper motor driven by discrete switches on the main
logic board to which it is connected through J117. A 1.0A non-replaceable
fuse protects the motor.
Transport/Line Feed Motor. This is a DC motor that drives the tape/enve-
lope transport as described earlier in this chapter. The transport moves the
media from the entry station (at PS1) to the print station, where it serves as
a line feeder, and, at the completion of printing, through the exit rollers out
to the stacker.
This motor is driven from the 27V rail through an integrated motor driver
mounted on the main logic board. It connects to the main logic board
through connector J115 and is protected by a 2.3A non-replaceable fuse.
Feeder Motor (DM400c/DM450c/DM475). This is a DC motor driven with
discrete devices resident on the feeder PCB. It is identical to the Transport/
Line Motor described above, except that it includes a thermistor device
(connected to J312) to protect the motor from over heating. There is also a
current limit protection circuit associated with this motor drive. The motor is
connected to the feeder PCB through J306 for DM400c/DM450c or through
J309 for the DM475. The feeder motor encoder is attached to this motor.
The motor drive is protected by a 3.2A non-replaceable fuse on the feeder
PCB.
Transport/Line Feed Disc Encoder. The encoder provides the quadrature
(two-channel) signals required for the motion control of the line feed motor.
The encoder has a resolution of 1651 lines (pulses). It connects to the main
logic board through J122.
Feeder Encoder (DM400c/DM450c/DM475). The system uses this encod-
er to provide motion control for the envelope to ensure that mail pieces feed
at the proper velocity. The feeder encoder sensor output is connected to the
feeder PCB through connector J302 for DM400c/DM450c or through J315
for the DM475.
Carriage Drive Motor. This motor moves the carriage that houses the ink
tank and print head back and forth between the print and the parked (home)
positions. During this process, the print head is wiped and cleaned as it
passes over the surface of the wiper blades mounted on the purge unit. The
carriage drive motor is a stepper type driven by an integrated motor driver
on the main logic board. The motor is connects to the main logic board
through J118 and is protected by a 1.8A non-replaceable fuse.
Purge Motor. This is an integral part of the purge unit and drives the cap,
wiper, print head lock and ink suction pump through a series of cams. See
paragraph 3.5.4 for more details. The purge motor is a stepper type driven
by discrete switches from the main logic board to which it is connected
through J116. The motor drive is protected by a 1.0A non-replaceable fuse.
3.6 Electronics
✍
TIP: See section 3.10
for specific Feeder/
WOW theory (includ-
ing sensors) specific to
DM475.
✍
TIP: The DM475 uses
the existing DM400c
autofeeder hardware,
print engine, modem,
USB and serial ports,
meter PSD, and tape
feeder.