Outline Of Assembly Operation; Assembly Main Components; Fig. 4-13 Illumination Assembly Main Components - Canon NP-70 Service Manual

NP -70
4.2 ILLUMINATION ASSEMBLY
4.2-1 OUTLINE OF ASSEMBLY OPERATION
This unit is installed under the copyboard glass so that as the Copyboard moves across the
assembly the sheet original can be illuminated and its image reflected to the drum surface
through the light chamber of the Optical Assembly.
The "Repaid-Start"method has been adopted for lamp excitation and operates as follows:
4-9
a) Before the copying process is started 8,5 VAC is applied to the filaments of the fluorescent
lamps. This voltage heats the filaments and releases low-energy-level free electrons.
b) The electromagnetic field radiator, to which 240VAC is continuously applied, generates an
electromagnetic field which additionally excites these electrons.
c) When copying begins, full AC voltage is applied to the filaments &ionization takes place
immediately to illuminate the original.
4.2-2 ASSEMBLY MAIN COMPONENTS
Base Plate
Light Reflector
Support Block
Electromagnetic
Field Radiator
Fig. 4-13 Illumination Assembly Main Components
Illumination
Lamps
Contact Housing
© CANON INC.
Second Printing,lune, 1974