
II-32
2.5.3
Developing
Developing causes the toner to be attracted to the electrostatic image on the drum so as
to transform it into a visible image.
The developer consists of a non-magnetic toner. The development roller is made of
conductive rubber and the supply roller (which is also made of conductive sponge) rotate
against each other. The toner is charged and carried from the supply roller to the
development roller. The toner adheres to the development roller and is conveyed to the
drum at an even thickness controlled by the blade. The toner is nipped between the
development roller and the drum and developed onto the latent image on the drum. The
electrostatic field between the drum and the development roller, which is DC-biased from
the high-voltage power supply, creates the electrostatic potential to attract toner particles
from the development roller to the latent image area on the drum surface.
Fig. 2-40
2.5.4
Transfer
(a)
Transfer process
After the drum has been charged and exposed, and has received a developed
image, the toner formed is transferred onto the paper by applying a negative
charge to the back of the paper. The negative charge applied to the paper causes
the positively charged toner to leave the drum, and adhere to the paper. As a
result, the image is visible on the paper.
(b)
Cleaning process of transfer roller
If the toner is not transferred onto the paper perfectly, it is possible that there may
be residual toner on the drum which will adhere to the transfer roller. The transfer
voltage changes to a positive voltage during non-printing rotation of the drum.
Therefore the transfer roller is cleaned by returning the positively charged toner
adhering to the transfer roller onto the photo-conductive drum.
(a) Transfer process [ON]
(b) Cleaning process [ON]
Drum
Erase lamp
(a) Collecting process
(b) Discharging process
Cleaning roller
Development
roller
DC-bias
SR-bias
Supply roller
Develop housing
Auger
Separator
Blade
Transfer roller
Toner
Summary of Contents for HL-1020
Page 1: ......
Page 36: ...II 20 Fig 2 22 shows the CDCC interface circuit Fig 2 22 HL 1050 ...
Page 37: ...II 21 1 3 10 Engine I O Fig 2 23 shows the engine interface circuit Fig 2 23 HL 820 1020 1040 ...
Page 38: ...II 22 Fig 2 24 shows the engine interface circuit Fig 2 24 HL 1050 ...
Page 67: ...III 18 4 PACKING Fig 3 32 Documents Accessory carton Pad Pad Printer Bag Carton ...
Page 101: ...CODE UK4007000 B48K312CIR NAME V 5 Appendix 5 Main PCB Circuit Diagram HL 820 1020 1040 1 2 ...
Page 102: ...Appendix 6 Main PCB Circuit Diagram HL 820 1020 1040 2 2 CODE UK4007000 B48K312CIR NAME A 6 ...
Page 103: ...Appendix 7 Main PCB Circuit Diagram HL 1050 1 5 CODE UK4041000 B512001CIR NAME A 7 ...
Page 104: ...Appendix 8 Main PCB Circuit Diagram HL 1050 2 5 CODE UK4041000 B512001CIR NAME A 8 ...
Page 105: ...Appendix 9 Main PCB Circuit Diagram HL 1050 3 5 CODE UK4041000 B512001CIR NAME A 9 ...
Page 106: ...Appendix 10 Main PCB Circuit Diagram HL 1050 4 5 CODE UK4041000 B512001CIR NAME A 10 ...
Page 107: ...Appendix 11 Main PCB Circuit Diagram HL 1050 5 5 CODE UK4041000 B512001CIR NAME A 11 ...
Page 108: ...Appendix 12 Panel Sensor PCB Circuit Diagram CODE UK4010000 B48K303CIR NAME A 12 ...
Page 117: ...Apr 98 84U005BE0 PARTS REFERENCE LIST MODEL HL 820 1020 1040 1050 R LASER PRINTER ...
Page 122: ...1 1 1 MODEL HL 1050 84U 861 101 103 104 84U 862 106 6 4 5 MAIN PCB HL 1050 OTHERS ISRAEL 3 ...
Page 135: ...CONTENTS LOWER TRAY UNIT List 1 Drawing 2 ...
Page 137: ... 2 GENERAL DRAWING MODEL LT 24CL 54S X06 4 3 1 6 5 2 7 ...
Page 214: ......
Page 296: ...USER S GUIDE A 12 HP LaserJet IIP 6P EPSON FX 850 IBM Propritner XL EPSON FX 850 ...