Sharp PC-1600

7-2. Physical Characteristics of the printer
The PTMPG printer is composed of five parts: a frame unit,
an X-direction drive unit, a Y-direction drive unit, a pen
drive mechanism & color-change mechanism, and a pen
take-out mechanism. Each part is described below.
1. The Frame unit
The frame unit consists of a right side-plate, a left side-
plate, support plate and paper guide. The lower end of the
frame is used for mounting.
2. The X-Direction Drive unit
The X-direction drive unit consists of an X stepping motor,
an idler gear, a pulley gear, a pulley support rest (Ieft)
unit, a pufley support rest (right) unit, a slider unit, and a
wire. The gear reduction ratio of the stepping motor and
pulley gear is 1: 13.9. A single pulse of the stepping motor
(18 degrees/360) moves the slider unit or pen by 0.2mm in
the X direction. Power transmission from the pulley gear
to the slider unit is made by the wire, which is tensioned
by a coil spring.
X Steppin9 Motor
Slider Unit Wire
3. The Y-Direction Drive unit
The Y-direction drive unit is the paper-feed mechanism.
It consists of a Y stepping motor, an id·ler gear, a platen
roller unit, a paper holder installing plate (feft), and a
paper holder installing plate (right). The reduction ratio
between the Y stepping motor (Y motor) and the platen
gear is 1;7.88. One pulse of the Y motor moves the platen
rollet, or recording paper, by 0.2mm in the Y direction.
Paper Holder
lnstatlinq
Plate (left)
~
Platen Roller unit
\
4. The Pen Drive Mechanism & Color-Change Mechanism
This part consists of two main blocks: the pen drive
mechanism and the color-change mechanism, each of which
is described below.
-
PC-l600
1) The Pen Drive Mechanism
The pen drive mechanism consists of a Z-motor unit, a
Z-cam gear, an ejection lever shaft unit, a roller lever
and a ball point pen.
The pen's up/down movements are performed by the
rotation of the cam gear, whose motive power is trans-
ferred to the ejection lever through a pin. Considering
the E point below as an origin, the pen comes down
when the cam gear rotates three (3) steps along Z (+)
direction, and the pen comes up when the cam gear
rotates three (3) steps from the pen-down position
along Z (-I direction.
(1) View of the Z-Cam Gear
3 steps 7 steps 15 steps
(2) Z-Cam Gear steps
2) The Color-Change Mechanism
The color change mechanism is composed 01 a Z-rnotor
unit, a Z-cam gear unit, an ejection Iever shaft unit, a
rotary holder which is in the slider unit, and a color-
change lever.
The color-change is performed by the movement of the
Zvcarn gear gram from E point to 0 point and then the
reciprocation of it between 0 and A points. The gear
of the rotary holder has 32 teeth, and eight (8) reci-
procations of the 15-step movement make for a color
change once.
5_ The Pen Take-Out Mechanism
The pen take-out mechanism is alever which is attached to
the slider unit. To replace the pen with a new one, first
press down the pen take-out lever. Then, pick up the pen
from the rotary holder and replace it. A pen can be re-
palced at any position on the slider unit.
-7:'l-