Overview And Operatingprincipleof The Printer - Sharp ER-04RP Service Manual

,..,,. . . . ... . . ..
. .....
ER+4RP
8. Overview and operating principle of the
printer
8-1.
Overview
8-1-1. Features
The DP614 printer is a compact serial dot printer, and has the follow-
ing features.
(1) Compact, light weight, and low power consumption.
(2) High speed printing, crisp printing by high reliability 7-pin head,
and bidirectional printing method.
(3) Paper insertion in both directions, from the rear and from the
bottom. (for friction type only)
8-1-2. General specification
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Printing method
Serial impact dot matrix printing method
Printing direction
Bi-directional (unidirectional for graphic printing)
Printing speed
3.0 lines/see. Al 070
(At motor voltage +25V, +25"C)
Print format
1) Character matrix 7x7 (including half dots)
2) Dot composition
180 (360) dots/line
Numbers in parentheses include half dots.
3) Print columns and character
size
40 columns 1.4(W) x 2.4(H)mm
Color change
Color change is accomplished by energizing the color change
solenoid.
1) Voltage: 24tl VDC
Resistance:
33A3Q (25tC)
Paper feed
1) Voltage:
24~~VDC (across solenoid terminals)
Resistance: 33*3Q (25"C)
2) Paper feed pitch
4.23mm (1/6")
2.82mm (1/9") for graphic type
3) Quick paper feed Approx. 18 lines/see.
Recording paper
1)
2)
3)
Type Friction type: Roll paper
76mmH.5mm (width)
@83mm(outer dia.)
Pin wheel type: Fan fold paper
Width 76mm (3") to 89mm (3.5")
Kinds of paper Plain paper and non-carbon paper
Recommended paper
(Cutforrn paper) 45-55kg/l 000 sheets(1091x788mm/sheet)
(Copy paper) Non-carbon paper
Friction type: One original + one copy
Pin wheel type: One original + two copies
Inking
Motor
Printhead
Total thickness 0.2mm max.
Special cartridge ribbon, re~black two-color or black
monocolor
DC brush motor
Voltage: 24~1VDC
Current: Peak current Approx. 1A
Average current 0.2A max.
Number of wires:9
Wire diameter:
().smm
Wire pitch: 0.353mm
Solenoid: Voltage 24*1 VDC
Resistance:
17Q (25"C)
11. Overall dimensions
137(W) x 136(D) x 63.5(H)mm
(5.4"(W) X 5.35"(D) X 2.5(H))
12. Weight
Approx. 690g (1.5 Ibs)
13. Reliability Printhead life:
50 million characters
Printer mechanism: MCBF 2.5 million lines
14. Operating temperature
o
to
+50"C
8-2. Mechanism and operating principle
8-2-1. Outline of mechanism
The printer mechanism consists of the following nine blocks.
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
Frame block
Motor block
Power transmission mechanism block
Sensor mechanism block
Head feed mechanism block
Printhead mechanism block
Paper feed mechanism block
Ribbon mechanism block
Color change mechanism block
8-2-2. Mechanism
and operating principle
Of the above nine blocks, seven mechanism blocks excluding the
frame and motor blocks are described next for their structures and
operating principles.
(1)
Power transmission mechanism block
This mechanism block is disposed en bloc on the right side of
the printer unit, and consists of a motor pinion fixed to the motor
shaft, a reduction gear, and a drive gear, plus four gear trains
coupled to the drive gear, i.e. a head feed gear train, a paper
feed gear train, a ribbon feed gear train, and a ribbon reset gear
train.
Reduction gear
gear
Head feed gear train
This gear train consists of a pulley drive gear, which is driven
by the drive gear, a drive pulley, and an idle pulley. The drive
pulley drives a timing belt SA to feed the printhead.
Drive gear
rive gear
Idle pulley
-14-