Feed Assembly; Platen Module; 24Vdc Stepper Motor; Lower Supply Guide And Bi-Cell Sensor - Monarch 9820 Service Manual

Functional Description

Ribbon Spool Drive Motors

wo DC ribbon drive motors are mounded to the back
of the module wall. Each motor drives a ribbon spool.
The motors are connected directly to the Control
Board Assembly via separate two-wire harness.
Supply Deflector and Bi-Cell Emitter
(IR LED)
See Chapter 8, "Supply Sensing Systems" for more
information.

Ribbon Transfer Rollers

The two ribbon transfer rollers allow ribbon tension
adjustments. Each roller has an eccentric which
allows slight skew adjustments to each, which in turn
affects the ribbon tension.
Functional Description
The print module, performs ribbon drive operations,
provides mechanical ribbon tension adjustments,
performs print functions, helps maintain supplies
tracking, and houses half of the sensor assembly. It is
controlled by the Control Board Assembly.

Ribbon Drive Operation

The ribbon drive operation is made up of two ribbon
spools, two 25Vdc drive motors, and two ribbon
transfer rollers. It is controlled by the Control Board
Assy. Each drive motor sends continuous information
to the Control Board Assy. where it is used to evaluate
ribbon conditions, maintain optimum ribbon tension,
and sense the end of ribbon condition. This system
eliminates the need for ribbon sensors.

Printing

The printhead has a line array of 832 dot elements
sized to produce 203 dots per inch. Printing occurs by
sending image data to the printhead one line at a
time. Each time a line of data is received,
corresponding dots on the printhead are heated to
create an image line on the stock. Successive image
lines generated across moving stock make up the total
image. The Control Board Assy. controls all image
data sent to the printhead, and regulates the energy
level of the printhead. Energy levels are raised and
lowered to create darker or lighter print respectively.

FEED ASSEMBLY

The feed module components are mounted on a metal
frame positioned beneath the Print module and
July 1998 TC9830SM Rev. B 7/98 Confidential
9820/9830/9835 Service Manual
fastened to the printer base. Components of the feed
module are:

Figure 2- 2. Feed Assembly

Platen Module

The platen rollers are on top of the feed module frame
just beneath the printhead. It is held in place by two
bearing blocks latched on the frame sides. The inner
side of the platen roller shaft extends through the
inside wall of the feed module where a drive gear is
attached.

24VDC Stepper Motor

The stepper motor is located behind the mid-frame of
the printer. Its drive shaft and gear extends through to
the space between the printer mid-frame and the feed
module frame.
Lower Supply Guide and Bi-Cell
Sensor
See Chapter 8, "Supply Sensing Systems" for more
information.

Printhead Latch

The printhead latch is spring loaded and mounted on
the outside of the feed module frame; within the latch
fascia. It locks the printhead in position.
Functional Description
The feed module transports supply through the printer
and across the printhead. It also maintaining proper
alignment, tension, and speed. This is accomplished
by sensing the stock position while securing the
printhead down onto the platen roller. Major functions
are supply feeding and supply sensing. See Chapter
8, "Supply Sensing Systems" for more information.
Bearing
Blocks
Spring
Latch
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